request vs solicitation

request and solicitation both are nouns.

Word	Noun	Adjective	Verb	Adverb
request	Yes	No	Yes	No
solicitation	Yes	No	No	No

As nouns, solicitation is a hyponym of request; that is, solicitation is a word with a more specific, narrower meaning than request:

request: a formal message requesting something that is submitted to an authority
solicitation: request for a sum of money

Other hyponyms of request include application, appeal, collection, ingathering, demand.

request (noun)	solicitation (noun)
the verbal act of requesting	the act of enticing a person to do something wrong (as an offer of sex in return for money)
a formal message requesting something that is submitted to an authority	an entreaty addressed to someone of superior status
	request for a sum of money

request (verb)	solicitation (verb)
express the need or desire for
ask (a person) to do something
inquire for (information)