threed

"If something's fast, why not just say so, instead of using the word performant?" For the same reason someone might say "Tommy was talented" instead of "Tommy played the piano and was also good at sports." You might want to be general, in some cases, instead of specific.

I've worked in computer science for over a decade and studied the subject at a university. In both environments this word was commonly used and accepted by professors and long-time computer scientists. Perhaps the confusion comes from business people using the term in a less precise way (see here: techopedia.com/definition/28231/performant). This "business" usage may be what the non-computer scientists in this forum have experienced. For anyone else who is wondering, be assured that in computer science this is a technical word with a precise meaning, whatever it may mean elsewhere.

@ConcreteGannet The concept between "x performs well" and "x is performant" is the same. The new concept I'm referring to is the performance of software. It is in this field that I have heard this word used so frequently, probably because there isn't a good, common adjective for describing this. I'm not surprised that the word sounds pretentious--jargon within a particular field often does; still, within the field, it is very useful. It's inconvenient and awkward to always have to phrase things using a verb.

If everyone avoids using a word until it becomes a word, will it ever become a word? This 'word' is very common in the field of computer science and fills a whole that is of course not supplied by an existing word because the exact concept did not exist until recently. Isn't that how new words are invented--we encounter new concepts and make new labels? It's either that or via slang.