sea cradle vs mollusk

sea cradle and mollusk both are nouns.

Word	Noun	Adjective	Verb	Adverb
sea cradle	Yes	No	No	No
mollusk	Yes	No	No	No

As nouns, mollusk is a hypernym of sea cradle; that is, mollusk is a word with a broader meaning than sea cradle:

sea cradle: primitive elongated bilaterally symmetrical marine mollusk having a mantle covered with eight calcareous plates
mollusk: invertebrate having a soft unsegmented body usually enclosed in a shell

Other hypernyms of sea cradle include mollusc, shellfish.

sea cradle (noun)	mollusk (noun)
primitive elongated bilaterally symmetrical marine mollusk having a mantle covered with eight calcareous plates	invertebrate having a soft unsegmented body usually enclosed in a shell