What part of speech is drydock?

Drydock can be categorized as a verb.

Parts of speech

1. drydock is a verb, present, 1st person singular of drydock (infinitive).
2. drydock is a verb (infinitive).

Verb
drydock - maneuver (a ship) into a drydock
Noun
drydock - a large dock from which water can be pumped out; used for building ships or for repairing a ship below its waterline