1862, from submerse or from Latin submers-, past participle stem of submergere + -ible. As a noun, from 1900, "a submersible craft." Alternative adjective submergible is attested from 1820, from submerge.
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.
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.
<a href="https://www.etymonline.com/word/submersible">Etymology of submersible by etymonline</a>
Harper, D. (n.d.). Etymology of submersible. Online Etymology Dictionary. Retrieved $(datetime), from https://www.etymonline.com/word/submersible