gate vs lock-gate

gate and lock-gate both are nouns.

Word	Noun	Adjective	Verb	Adverb
gate	Yes	No	Yes	No
lock-gate	Yes	No	No	No

As nouns, lock-gate is a hyponym of gate; that is, lock-gate is a word with a more specific, narrower meaning than gate:

gate (noun)	lock-gate (noun)
a movable barrier in a fence or wall	a gate that can be locked
a computer circuit with several inputs but only one output that can be activated by particular combinations of inputs
passageway (as in an air terminal) where passengers can embark or disembark
total admission receipts at a sports event

gate (verb)	lock-gate (verb)
restrict (school boys') movement to the dormitory or campus as a means of punishment
control with a valve or other device that functions like a gate
supply with a gate