botany vs algology

botany and algology both are nouns.

Word	Noun	Adjective	Verb	Adverb
botany	Yes	No	No	No
algology	Yes	No	No	No

As nouns, algology is a hyponym of botany; that is, algology is a word with a more specific, narrower meaning than botany:

Other hyponyms of botany include mycology, pomology, palaeobotany, paleobotany, phycology, pteridology.

botany (noun)	algology (noun)
the branch of biology that studies plants	the branch of botany that studies algae
all the plant life in a particular region or period