(noun; Latin sutura
, seam): 1. Line of junction of 2 parts generally immovably connected.
2. (Arthropoda: Crustacea) In Cirripedia, a line or seam at the juncture of two compartmental plates; weakly calcified areas of the integument for separation at ecdysis.
3. (Arthropoda: Insecta) Grooves marking the line of fusion of two former plates; a narrow membranous area between sclerites; line of juncture of elytra in Coleoptera.
4. (Mollusca: Gastropoda) The continuous spiral line on the shell surface where whorls adjoin.