Bashful means shy and easily embarrassed. A bashful smile, look bashful, not at all bashful.
It is warmer than shy and slightly old-fashioned, and it suits children, first meetings and the moment somebody is praised. Not bashful about it is the standard ironic use, meaning quite the opposite. Note bashfully, bashfulness; and that the word is a shortened form of abashed plus -ful, so being bashful is being full of abashment — which is a neat piece of construction.
1adjectivebashfulShy and easily embarrassed.
“She gave a bashful laugh and turned red when he praised her singing.”
bashful is a quality of shyness.
The word is a sixteenth-century clipping of abashed plus -ful. Abash came from Old French esbahir, to astound, so bashful is literally full of being taken aback.
16th-century apheresis of abashed + ful.
Etymology from Wiktionary, CC BY-SA