wire vs night letter

wire and night letter both are nouns.

Word	Noun	Adjective	Verb	Adverb
wire	Yes	No	Yes	No
night letter	Yes	No	No	No

As nouns, night letter is a hyponym of wire; that is, night letter is a word with a more specific, narrower meaning than wire:

Other hyponyms of wire include cable, cablegram, overseas telegram, letter telegram.

wire (noun)	night letter (noun)
ligament made of metal and used to fasten things or make cages or fences etc	a cheaper form of telegram sent for delivery the next day
a metal conductor that carries electricity over a distance
a message transmitted by telegraph
the finishing line on a racetrack

wire (verb)	night letter (verb)
equip for use with electricity
send cables, wires, or telegrams
fasten with wire
string on a wire
provide with electrical circuits