Nostril

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Old English nosterl, nosthyrl, from nosu ‘nose’ + thȳr(e)l ‘hole’.

wiktionary

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From earlier nosthril, nosethrill, from Middle English nostril, nostrel, nosterl, nosthirl, nosethril, nosethirl, noosthril, nosethyrl, nosethurl, nesethirl, nesthyrylle, nasethirl, nesethrull, from Old English nosþȳrel, equivalent to nose +‎ thirl(“hole”). Compare Old Frisian nosterle(“nostril”), modern West Frisian noaster(“nostrill”). Compare also Middle Low German noster(“nostril”), from Proto-Germanic *nustriz(“nostril”).

etymonline

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nostril (n.)

"one of the external openings of the nose, a nasal orifice," late 14c., nostrille, from Old English nosþyrl, nosðirl, literally "the hole of the nose," from nosu "nose" (from PIE root *nas- "nose") + þyrel "hole" (from PIE root *tere- (2) "cross over, pass through, overcome"). For metathesis of -r- and vowel, see wright. After the second element became obsolete as an independent, its form was corrupted in the compound.