1 compliment unduly; overpraise, esp. for gain or advantage.
2 (usu. refl.; usu. foll. by that + clause) please, congratulate, or delude (oneself etc.) (I flatter myself that I can sing).
3 a (of a colour, a style, etc.) make (a person) appear to the best advantage (that blouse flatters you). b (esp. of a portrait, a painter, etc.) represent too favourably.
4 gratify the vanity of; make (a person) feel honoured.
5 inspire (a person) with hope, esp. unduly (was flattered into thinking himself invulnerable).
6 please or gratify (the ear, the eye, etc.).
Phrases and idioms:
flattering unction a salve that one administers to one's own conscience or self-esteem (Shakesp. esp. Hamlet III. iv. 136).
Derivatives:
flatterer n. flattering adj. flatteringly adv.
Etymology: ME, perh. rel. to OF flater to smooth
Useful english dictionary. 2012.