send off vs despatch

send off is not a noun while despatch is a noun.

Word	Noun	Adjective	Verb	Adverb
send off	No	No	Yes	No
despatch	Yes	No	Yes	No

As verbs, send off and despatch are synonyms defined as:

Other synonyms of send off include dispatch.

send off (noun)	despatch (noun)
	the act of sending off something
	killing a person or animal
	the property of being prompt and efficient
	an official report (usually sent in haste)

send off (verb)	despatch (verb)
transfer	send away towards a designated goal
throw, send, or cast forward
send away towards a designated goal