Reptile comes from Late Latin reptile ('creeping thing'), from Latin reptilis ('creeping'), from repere ('to creep, crawl'). The historical chain includes Latin reptile, Latin repere, and Proto-Indo-European *rep-. Older glosses in the chain include "creeping thing", "creeping", and "to creep, crawl", which help explain the semantic range of the modern word. Morphologically, reptile is best read as borrowing, yielding an English noun and adjective shaped by both form history and later usage. In current English it functions as a noun and adjective, with the sense "a cold-blooded scaly vertebrate such as a snake, lizard, or crocodile". English derivatives include reptilian and reptilelike; related forms include reptant and reptilian. The result is an English noun and adjective whose etymology preserves the older forms while supporting the word's specialized modern meaning.