Other forms: advised, advising, advises
To advise is to tell somebody what you think they should do. Advise him to wait, I would advise against it, as advised.
The spelling is the trap: advise with an s is the verb and advice with a c is the noun — she advised me, her advice was good. The patterns are advise somebody to do something and advise against something. In formal correspondence advise also means to inform: please advise us of any change. Note adviser and advisor, both accepted spellings, and advisory, meaning giving advice rather than orders.
1verbadviseTo tell somebody what you think they should do.
“She advised him to say nothing at all.”
2verbinformTo inform somebody officially.
“Please advise us of any change of address.”
Too few real examples of this word to estimate which sense is commonest.
advise is a way of guiding.
Old French aviser comes from a phrase meaning it seems to me, from Latin visum, seen. Advice and advise both descend from somebody's view of a matter, which is a fair account of what advice is.
Proto-Indo-European
*weyd-
Middle English
avisen
English, today
advise
From Middle English avisen. From Middle English avisen (“to perceive, consider, inform”), from Old French aviser, from avis, or from Latin advisō, from ad + visō. See also advice.
Etymology from Wiktionary, CC BY-SA