drydock vs graving dock

drydock and graving dock both are nouns.

Word	Noun	Adjective	Verb	Adverb
drydock	Yes	No	Yes	No
graving dock	Yes	No	No	No

As nouns, drydock and graving dock are synonyms defined as:

drydock and graving dock: a large dock from which water can be pumped out; used for building ships or for repairing a ship below its waterline

Other synonyms of drydock include dry dock.

drydock (noun)	graving dock (noun)
a large dock from which water can be pumped out; used for building ships or for repairing a ship below its waterline	a large dock from which water can be pumped out; used for building ships or for repairing a ship below its waterline

drydock (verb)	graving dock (verb)
maneuver (a ship) into a drydock