noun
reptile
General term for reptiles; used in biological and everyday contexts.
爬虫類にはヘビやトカゲが含まれる。
Reptiles include snakes and lizards.
爬虫類 is the full term for 'reptiles' as a biological class; 爬虫 is a shorter, less common form often used in compounds.
From Chinese 爬蟲／爬虫 (páchóng), meaning 'reptile'. The kanji 爬 means 'crawl' and 虫 means 'insect' or 'creature'.