What do you call...

[alice]

The opposite of a factitive verb, i.e. a verb which removes or lessens a property of its object, for example "decontaminate" or "un-whiten"? Is it "unfactitive", "fictionitive", or something else?

[Linguoboy]

Privative?

[Kuchigakatai]

Those examples don't seem to me to be the opposite of factitive verbs. In English grammar, factitive verbs take two objects and transform the first object so that it has the second object as a property. The classic example is "elect" for some weird reason, but more natural/common examples are "make" and "call".

My classmates elected me class representative.
I made Xwtek the new paragon of the ideal conlanger.
Don't call my friend a horrible person.

In French grammar, the factitive is a causative construction (passive for the pivot) involving a reflexive faire 'to do' and the infinitive: je me fais couper les cheveux là-bas 'I get my hair cut there'. As you can see, English has something similar involving "have/get", but in English grammar this is just called the "have something done" construction.)

I don't know what the opposite of factitive verbs would be. Maybe verbs that "un-declare" something to be something. "We now undeclare this word kosher" (we now declare this word is not kosher).

Regarding your examples, I think these still fall in the general category of causative verbs in normal linguistics, just like contaminate and whiten... You might need a novel label in your case. Here are some good candidates:

privative
retractive
deductive
reductive
attenuative
minorative

Or, if you want to needlessly show off your Latin by using stems not commonly seen in English:

levative
relevative
tenuative
lenitive
delenitive
mollitive (two l's)
amolitive (one l)
submotive
exceptive
exemptive
sublative
abditive
demptive

Or, if you still want to show off your Latin BUT also confuse the hell out of people:

ablative
depressive
amotive

By the way, I have no problem with the likes of "decausative", "uncausative", or even "defactitive" or "unfactitive". These are definitely not Latin stems, but it doesn't matter.

[Salmoneus]

Those examples don't seem to me to be the opposite of factitive verbs. In English grammar, factitive verbs take two objects and transform the first object so that it has the second object as a property. The classic example is "elect" for some weird reason, but more natural/common examples are "make" and "call".

My classmates elected me class representative.
I made Xwtek the new paragon of the ideal conlanger.
Don't call my friend a horrible person.

I have two objections.

First, traditionally, and in the first two examples you give, the second object is not a property of the first, but an identity. "We painted the horse blue" is giving the horse a property, changing how the horse is; but "We elected the horse senator" is giving it a new identity, it's changing what the horse is.

Second, "call" in the sense you use it isn't a factitive by either of our definitions, becaus 'a horrible person' is not de re either a property or an identity of your friend just because someone calls him that. It's closer to "think he's a horrible person", "find him a horrible person" and so on - they're verbs of apprehension, not verbs of factition.

Simple test: if X [factitive verbs] Y a Z, then there is a Z. When your classmates elect you class representative, there is a class representative (and you are they). If Xwtek is made a paragon, there is a paragon (it's Xwtek). But if I call you a unicorn, that doesn't make unicorns real!

However, "call" may arguably factitive when it's used as a colloquial synonym of "name" - as in, "we called our son John", or "we called our new country Bolivia", where "call" is understood as "fix a name to". [although, unlike 'name', it remains ambiguous - we called our son John although his name was Peter, or we called our new country Bolivia, just to annoy the Bolivian ambassador, etc.]

[Vijay]

I made Xwtek the new paragon of the ideal conlanger.

[Travis B.]

By the way, I have no problem with the likes of "decausative", "uncausative", or even "defactitive" or "unfactitive". These are definitely not Latin stems, but it doesn't matter.

Note that there is such a thing as an anticausative verb which is a completely distinct idea from this, so one may want to avoid "decausative" or "uncausative".

[Pabappa]

The term "becausative" appears in a grammar of Inuktitut, used for constructions like "I went to the store for milk" and "I was screaming because i lost my toe".

[akam chinjir]

The term "becausative" appears in a grammar of Inuktitut, used for constructions like "I went to the store for milk" and "I was screaming because i lost my toe".

Inspired by Aristotle's four becauses?

[Linguoboy]

So it's been a while since we had a "what do you call this thing?" question. It's another kitchen query: What do you call a flat piece of metal which you place food upon before putting it into a full-sized oven (domestic or industrial)? If you have more than one term, what governs their usage?

[Vijay]

A tray?

I've never seen a completely flat thing being put into the oven at our house at least, though. It's always rimmed, I think (IIRC what "rimmed" means).

[Yalensky]

I'm pretty sure I'd all that a baking sheet, maybe a cookie sheet if I'm baking cookies. But I hardly ever bake so I'm relying on my memories of what my mother calls it.

[Vijay]

Honestly, I guess my parents would call it a baking sheet as well, but to me, a baking sheet isn't made of metal.

EDIT: Or maybe I've just always confused baking sheets with parchment paper.
EDIT2: Like, I know unambiguously what "parchment paper" is, but the same is definitely not true of "baking sheet." "Tray" for me is far less confusing.

[zompist]

Cookie sheet, even if it's not for cookies.

(But if the rim is 2" high or so, it's a baking pan.)

[Linguoboy]

Honestly, I guess my parents would call it a baking sheet as well, but to me, a baking sheet isn't made of metal.

When I was thinking about this earlier, it struck how odd a compound "baking sheet" is. Like someone hearing the term for the first time could be forgiven for thinking it's piece of cloth that you put over baked goods while they're cooling to keep the flies or something. Using it as a term for a parchment paper placed in a baking tray makes a great deal of sense, too.

In my household, these were "cookie sheets" it they were unrimmed. We had one or two with rims and we called them "jelly roll pans" even though, in all my years, I've never seen anyone in my family actually use one to bake a jelly roll. "Baking sheet" for me is a word I know from reading cookbooks, but a friend of mine was insistent that a "baking sheet" is always unrimmed and that the proper term for a rimmed baking sheet is "sheet pan".

[anteallach]

"Baking tray". I'm familiar with "baking sheet" but don't use it myself.

All the ones I've used are rimmed.

[alice]

"Baking tray", as the LORD wills.

[vegfarandi]

OK all of this is making my head spin with possibilities for cool things to do with factitive verbs. Anyone have some kind of survey of different ways these work in different languages?

In Icelandic, the traditional analysis is that a type of complement called objective complement is added after the object, which agrees with the object in case if it's an adjective:

við máluðum hestinn rauðan
we-NOM painted horse-ACC-DEF red-ACC-MASC-STRONG_DECLENSION
we painted the horse red

If I remember my Latin correctly, it worked similarly.

Anyone have examples from more exotic languages?

[Linguoboy]

In Icelandic, the traditional analysis is that a type of complement called objective complement is added after the object, which agrees with the object in case if it's an adjective:

við máluðum hestinn rauðan
we-NOM painted horse-ACC-DEF red-ACC-MASC-STRONG_DECLENSION
we painted the horse red

If I remember my Latin correctly, it worked similarly.

Anyone have examples from more exotic languages?

I don't know how "exotic" is is, but I don't think this kind of construction works at all in Irish. The only way I know to phrase this sentence is:

Chuireamair péint dhearg ar an gcapall.
put-1P.PST paint red-F on the horse-DAT
We painted the horse red.

The same construction (with a different verb) is used to express "call somebody something":

Do thugamair Deargán ar an gcapall.
give-1P.PST red-DIM on the horse-DAT
We called the horse "Red".

For expressions like "he thought it strange" or "I found that difficult", a different idiom entirely is used:

B'ail leis é.
COP.PST strange with-3SM 3S.ACC
"He thought it strange."

Ba dheacair dom sin a chreidiúint.
COP.PST difficult to-1S that LINK believe-VN
"I found that hard to believe".

[cedh]

OK all of this is making my head spin with possibilities for cool things to do with factitive verbs. Anyone have some kind of survey of different ways these work in different languages?

Many languages use a separate case for the resultative secondary predicate. In this Hungarian example it's the sublative:

Mari piros-ra festette a falat.
Mary red-SUBL painted.3SG the wall.ACC
‘Mary painted the wall red.’

In this Japanese example it's the dative:

Taro-ga yuka-o kirei-ni migaita.
Taro-NOM floor-ACC clean-DAT polish.PAST
‘Taro polished the floor clean’

The situation in Japanese seems to be more complex though, because there are several different types of adjectives, some of which inflect more like verbs. Apparently, for some words it's common to use the ‘continuative’ suffix -ku, as in the following example. Maybe someone else with better knowledge of Japanese can say more about this?

Mary-ga kami-o mizika-ku kitta.
Mary-NOM hair-ACC short-CONTIN cut.PAST
‘Mary cut her hair short’

Biak (Austronesian) expresses resultatives with stative verbs that inflect for person and number, and subordinates them to the ‘consequential’ particle fa:

P<y>am-i fa i-mar.
<3SG>shoot-3SG CONSEQ 3SG-dead
‘She shot him dead.’

[hwhatting]

Many languages use a separate case for the resultative secondary predicate. In this Hungarian example it's the sublative:

Russian generally uses the instrumental case for this:
Они выбрали Петра председателем.
they-NOM elected Peter-ACC chairman-INSTR
They elected him chairman.

Они сделали его сумасшедшим.
they-NOM made him (ACC) crazy-INSTR
They made / drove him crazy.

German, OTOH, uses different strategies depending on whether the secondary predicate is a noun or an adjective. Adjectives have the uninflected predicateive form:
Sie malten das Pferd rot an. Sie machten ihn verrückt.
They painted (anmalen) the horse red. They made him crazy.

Nouns take the preosition zu "to" and the dative case:
Sie wählten ihn zum Vorsitzenden. Sie machten ihn zum Klassensprecher.
They elected him to-Article.DAT chairman-DAT. They made him to-Article.DAT class-representative-DAT.