Learn English – the difference between “quicker” and “faster”

@Manoochehr doesn't quite catch the meaning of sardonic. It means "grimly mocking or cynical." My Webster's gives its origin as

mid 17th cent.: from French sardonique, earlier sardonien, via Latin from Greek sardonios ‘of Sardinia,’ alteration of sardanios, used by Homer to describe bitter or scornful laughter.

It really doesn't carry the connotation of superiority or low opinion all by itself, although such feelings may accompany it.

Sardonic is in fact distinct from sarcastic but not by much, and many people use the two as if they are interchangeable, which, strictly speaking, they are not. Sardonic is more extreme and negative, and one can be sarcastic without being sardonic, and vice-versa.

The meanings of jargon terms often have essentially nothing to do with the meanings of the English words they're made from. Nowhere is this more the case than in mathematics.

I would use whichever term seems better established—regardless of whether it sounds artificial to native English speakers who aren't mathematicians—so as to give the reader the best possible chance to figure out what I'm talking about.

Updated: I should just answer your question. To my ear, there is a verb filter, and a count noun filter. There is also a non-count noun filtration. (You can count coffee filters, but the filtration of water through coffee grounds isn't something you can count.) So already the mathematical use of filtration as a count noun ("a filtration") differs from the everyday use.

I am pretty sure I never heard the verb filtrate used in everyday English until I started searching for such uses just now. A Google search for filtrated hits mainly dictionary sites. At the moment, the first non-dictionary hit is a link to this question! I can confirm that to my ear, it's hardly a word, and it sounds weird and artificial. Filtered sounds much nicer to me. It is an actual common, everyday word (and, correspondingly, gets hundreds of times as many Google hits).