wharf vs tie up

wharf is a noun but tie up is not a noun.

Word	Noun	Adjective	Verb	Adverb
wharf	Yes	No	Yes	No
tie up	No	No	Yes	No

As verbs, tie up is a hypernym of wharf; that is, tie up is a word with a broader meaning than wharf:

Other hypernyms of wharf include berth, moor.

wharf (noun)	tie up (noun)
a platform built out from the shore into the water and supported by piles; provides access to ships and boats

wharf (verb)	tie up (verb)
moor at a wharf	secure with or as if with ropes
discharge at a wharf	finish the last row
come into or dock at a wharf	restrain from moving or operating normally
store on a wharf	secure in or as if in a berth or dock
provide with a wharf	invest so as to make unavailable for other purposes