-ile

Also ‑il and ‑ility

Forming adjectives and some nouns.

Via French from Latin ‑ilis.

Most words in ‑ile from this source are adjectives: agile, docile, ductile, fertile, fragile, juvenile, mobile, versatile, volatile. Several in statistics derive from Latin ordinal numerals, as in decile, each of ten equal groups into which a population can be divided; others are quartile, quintile, and percentile. A few nouns in ‑ile come from Latin words in ‑ilis: reptile (Latin reptilis, from repere, crawl), textile (Latin textilis, from texere, to weave). Others (like exile, facsimile, and imbecile) come from different Latin sources.

A few nouns in ‑il also derive from Latin ‑ilis (fossil, Latin fossilis, dug up; utensil, Latin utensilis, usable). However, most nouns in this ending derive from a variety of other sources, some from Old English (nostril), others from various French and Latin sources (fibril, lentil). The only common adjective in ‑il derived from a Latin word in ‑ilis is civil.

Abstract nouns are formed from adjectives in either ‑ile or ‑il by adding ‑ity: agility, civility, mobility, volatility.