"Performant" is a word in German. It translates to exact what "perfomant" would mean in english if it were an english word. The funny thing is, google translate, translates the german word "performant" to the english word "performant". https://translate.google.com/?hl=de#de/en/per%C2%ADfor%C2%AD...
> performant is not considered a real word in English, although I commonly see it used...
This is close to being a contradiction in terms. The purpose of words is to communicate, and if a word is being successfully used to communicate -- which clearly it is -- what exactly does it mean to say that isn't "considered a real word"?
Also, "Considered" by whom? The dictionary? Dictionaries are descriptivist -- they record usage, they don't prescribe it [0]. If it isn't in the dictionary yet, that's only because the usage hasn't been used widely and/or for long enough that it meets the inclusion criteria [1].
(As it happens, "performant" is at the stage where it is starting to pass those thresholds, and is now in the OED [2])
> (As it happens, "performant" is at the stage where it is starting to pass those thresholds, and is now in the OED [2])
Strictly speaking, I don't believe your [2] is the OED. It's "Oxford Living Dictionaries", which I assume tries to be more current/dynamic, but might be regarded as less authoritative.
Interestingly, the word "performant" is in the OED itself, with the earliest citation being from 1809 -- but it is listed only as a noun, meaning "A person who performs a duty, ceremony, etc., a performer", not the adjectival usage under discussion here.
