capitulum vs treetop

capitulum and treetop both are nouns.

Word	Noun	Adjective	Verb	Adverb
capitulum	Yes	No	No	No
treetop	Yes	No	No	No

As nouns, treetop is a hypernym of capitulum; that is, treetop is a word with a broader meaning than capitulum:

capitulum: an arrangement of leafy branches forming the top or head of a tree
treetop: the upper branches and leaves of a tree or other plant

Other hypernyms of capitulum include crown.

capitulum (noun)	treetop (noun)
a dense cluster of flowers or foliage	the upper branches and leaves of a tree or other plant
fruiting spike of a cereal plant especially corn
an arrangement of leafy branches forming the top or head of a tree