[spoiler]yiff  1) (noun) Sound supposedly made by mating arctic foxes.  2) (acronym) (or more backronym) YIFF or Y. I. F. F. - "Young Incredibly -blam!-able Furry"  3) (proper name) YIFF sound server. Program for Linux to help handle audio.  4) (noun) More or less (usually more) sexual act. Commonly used by furries, usually denotes standard intercourse but may denote any kind of sexual behaviour between any type and number of parties (imaginary anthro creatures, humans, animals, even inanimate objects like plushies). Antonym: Yerf.  5) (verb) Like in meaning 4, "to yiff".  6) Furry (or otherwise) artwork depicting yiff as in meaning 4.  7) Expression of joy (by furries)  8) Non-invasive question about sexual feelings/will to mate.[/spoiler]