1an idea, feeling, or opinion about something or someone, especially one formed without conscious thought or on the basis of little evidence:his first impressions of Manchester were very positiveI got the impression that he was sorely disappointed
an effect produced on someone:her courtesy had made a good impression
[mass noun] a difference made by the action or presence of someone or something:the floor was too dirty for the mop to make much impression
2an imitation of a person or thing, done to entertain:he did an impression of Shirley Bassey
3a mark impressed on a surface:the impression of his body on the leaves
Dentistry a negative copy of the teeth or mouth made by pressing them into a soft substance.
4a graphic or pictorial representation of someone or something:police issued an artist’s impression of the attacker
5the printing of a number of copies of a book, periodical, or picture for issue at one time.
[usually with modifier] chiefly British a particular printed version of a book, especially one reprinted from existing type, plates, or film with no or only minor alteration:a copy of the first impression
a print taken from an engraving.
6an instance of a pop-up or other Web advertisement being seen on an Internet user’s monitor.
under the impression that
believing, mistakenly or on the basis of little evidence, that something is the case:he was under the impression that they had become friends
