sedimentary adj.

1540s, "matter which settles by gravity to the bottom of water or other liquid," from French sédiment (16c.) and directly from Latin sedimentum "a settling, sinking down, subsidence," from stem of sedere "to settle, sit" (from PIE root *sed- (1) "to sit"). Especially in geology after 1680s.

adjective and noun word-forming element, in most cases from Latin -arius, -aria, -arium "connected with, pertaining to; the man engaged in," from PIE relational adjective suffix *-yo- "of or belonging to." The neuter of the adjectives in Latin also were often used as nouns (solarium "sundial," vivarium, honorarium, etc.). It appears in words borrowed from Latin in Middle English. In later borrowings from Latin to French, it became -aire and passed into Middle English as -arie, subsequently -ary.