midwatch vs middle watch

midwatch and middle watch both are nouns.

Word	Noun	Adjective	Verb	Adverb
midwatch	Yes	No	No	No
middle watch	Yes	No	No	No

As nouns, midwatch and middle watch are synonyms defined as:

midwatch and middle watch: a watch during the night (as from midnight to 8 a.m.)

Other synonyms of midwatch include graveyard watch, night watch.

midwatch (noun)	middle watch (noun)
a watch during the night (as from midnight to 8 a.m.)	a watch during the night (as from midnight to 8 a.m.)