neap vs high tide

neap and high tide both are nouns.

Word	Noun	Adjective	Verb	Adverb
neap	Yes	No	No	No
high tide	Yes	No	No	No

As nouns, high tide is a hypernym of neap; that is, high tide is a word with a broader meaning than neap:

neap: a less than average tide occurring at the first and third quarters of the moon
high tide: the tide when the water is highest

Other hypernyms of neap include high water, highwater.

neap (noun)	high tide (noun)
a less than average tide occurring at the first and third quarters of the moon	the tide when the water is highest