• (n.) A secondary mouth fold developed at the base of each of the armlike lobes of the manubrium of many rhizostome medusae. See Illustration in Appendix.
Scap'u·let noun [ Dim. of scapula .] (Zoology) A secondary mouth fold developed at the base of each of the armlike lobes of the manubrium of many rhizostome medusæ. See Illustration in Appendix.