mail out vs send out

mail out and send out both are verbs.

Word	Noun	Adjective	Verb	Adverb
mail out	No	No	Yes	No
send out	No	No	Yes	No

As verbs, send out is a hypernym of mail out; that is, send out is a word with a broader meaning than mail out:

mail out: transmit by mail
send out: to cause or order to be taken, directed, or transmitted to another place

Other hypernyms of mail out include send.

mail out (verb)	send out (verb)
transmit by mail	to cause or order to be taken, directed, or transmitted to another place