semiaquatic vs subaquatic

semiaquatic and subaquatic both are adjectives.

Word	Noun	Adjective	Verb	Adverb
semiaquatic	No	Yes	No	No
subaquatic	No	Yes	No	No

As adjectives, semiaquatic and subaquatic are synonyms defined as:

semiaquatic and subaquatic: partially aquatic; living or growing partly on land and partly in water

semiaquatic (adjective)	subaquatic (adjective)
partially aquatic; living or growing partly on land and partly in water	partially aquatic; living or growing partly on land and partly in water
having an aquatic early or larval form and a terrestrial adult form	growing or remaining under water