submergible vs submersible

submergible

noun
  • Synonym of submersible 

adj
  • Synonym of submersible 

submersible

noun
  • A term used primarily by some navies for nuclear submarines, termed "true submersibles", because they cannot retroactively declare that their non-nuclear submarines should be called by a different name. 

  • A small nonmilitary, non-nuclear submarine for exploration. 

  • A very small "baby" submarine designed for specific localized missions, usually while tethered to a submarine or ship for life support and communications. Slang synonyms: midget-submarine, anchor. 

  • A retroactive term used for non-nuclear submarines; nuclear submarines are termed "true submarines". 

adj
  • Able to be submerged. 

How often have the words submergible and submersible occurred in a corpus of books? (source: Google Ngram Viewer )