fir

adj

1. Initialism of finite impulse response; that has impulse response (or response to any finite length input) of finite duration.

noun

Etymology: From Middle English firre, from Old English fyrh, furh, as in furhwudu (“pinewood”), from Proto-West Germanic *furhu, from Proto-Germanic *furhō, *furhijǭ, from Proto-Indo-European *pŕ̥kʷeh₂, from *pérkʷus (“oak”). Possibly conflated during Middle English with Old Norse fýri (as in fýriskógr (“pine-wood”). Germanic cognates include Dutch vuren, Low German Fuhr, German Föhre (“pine”), Danish fyr). Outside of Germanic, compare Italian (Trentino) porca (“fir”), Latin quercus (“oak”), Albanian shpardh, shparr (“Italian oak”), Punjabi ਪਰਗਾਇ (pargāī, “holm oak, Quercus baloot”)). Related to frith.

1. A conifer of the genus Abies.

   “A beech wood with silver firs in it rolled down the face of the hill, and the maze of leafless twigs and dusky spires cut sharp against the soft blueness of the evening sky.”

2. Any pinaceous conifer of related genera, especially a Douglas fir (Pseudotsuga) or a Scots pine (Pinus sylvestris).

   “we shall find a spot that is sheltered and snug enough, sir. There is a dry fir-wood just ahead, if I remember rightly.”

   “I can almost smell the fir scent… resinous, pungent.”

3. Wood of such trees.