submersible (adj.)

early 15c., "to submerge, plunge" (transitive), from Latin submersus, past participle of submergere (see submerge). Modern use (18c.) might be a back-formation from submersion. Related: Submersed; submersing.

word-forming element making adjectives from verbs, borrowed in Middle English from Old French -ible and directly from Latin adjective suffix -ibilis (properly -bilis); see -able.

c. 1600 (transitive), from French submerger (14c.) or directly from Latin submergere "to plunge under, sink, overwhelm," from sub "under" (see sub-) + mergere "to plunge, immerse" (see merge). Intransitive meaning "sink under water, sink out of sight" is from 1650s, made common 20c. in connection with submarines. Related: Submerged; submerging.