English
reptilious
From reptile + -ious, replacing earlier adjectival reptile and reptitious.
Formed from reptile + -ious
Proto-Indo-European *rep- ‘to creep, slink’
…
Late Latin reptilis ‘creeping’
Late Latin rēptile ‘a reptile’
Old French reptile
Middle English reptil
English reptile
Today it means
adj Synonym of reptile: creeping, crawling.
Language periods are conventional ranges, not dates for this word.
Etymograph / reptilious