mandibula vs lower jawbone

mandibula and lower jawbone both are nouns.

Word	Noun	Adjective	Verb	Adverb
mandibula	Yes	No	No	No
lower jawbone	Yes	No	No	No

As nouns, mandibula and lower jawbone are synonyms defined as:

mandibula and lower jawbone: the jaw in vertebrates that is hinged to open the mouth

Other synonyms of mandibula include jawbone, jowl, lower jaw, mandible, mandibular bone, submaxilla.

mandibula (noun)	lower jawbone (noun)
the jaw in vertebrates that is hinged to open the mouth	the jaw in vertebrates that is hinged to open the mouth