Decent
mid 16th century (in the sense ‘suitable, appropriate’): from Latin decent- ‘being fitting’, from the verb decere .
wiktionary
From Middle French décent, or its source, Latin decēns, present participle of decet(“it is fitting or suitable”), from Proto-Indo-European *deḱ-(“to take, accept, to receive, greet, be suitable”) (compare Ancient Greek δοκέω(dokéō, “I appear, seem, think”), δέχομαι(dékhomai, “I accept”); Sanskrit दशस्यति(daśasyáti, “shows honor, is gracious”), दाशति(dāśati, “makes offerings, bestows”)). Meaning ‘kind, pleasant’ is from 1902.
etymonline
decent (adj.)
1530s, "proper to one's station or rank," also "tasteful, proper with regard to modesty or social standards," from French décent, or directly from Latin decentem (nominative decens) "becoming, seemly, fitting, proper," present participle of decere "to be fitting or suitable" (from PIE *deke-, from root *dek- "to take, accept"). Related: Decently.
Meaning "kind, pleasant" is from 1902. Meaning "moderate, respectable, good enough" is by 1711. Are you decent? "are you dressed?" (1949) was originally backstage theater jargon.