Dictionary

(of people or behaviour) Overly bold or self-assertive to the point of being insensitive, tactless or impudent; shameless.

Example: a brash young businessman; a brash tabloid; a brash sense of humour

(of actions) Overly bold, impetuous or rash.

(of things) Bold, bright or showy, often in a tasteless way.

Example: brash colours; a brash perfume

Brittle (said e.g. of wood or vegetables).