of, pertaining to, or characterized by impertinence or effrontery

The student was kept late for impudent behavior.

Obsolete . shameless or brazenly immodest.

adjective

humble , modest , polite , retiring

adjective

arrant , audacious , barefaced , blatant , boldfaced , brassy , brazen , bumptious , cheeky * , cocky * , contumelious , cool * , flip * , forward , fresh , immodest , impertinent , insolent , nervy * , off-base , overbold , pert , presumptuous , procacious , rude , sassy * , saucy * , smart * , smart-alecky , unabashed , unblushing , wise * , assuming , assumptive , bold , brash , cheeky , familiar , malapert , nervy , overconfident , presuming , pushy , sassy , saucy , smart , arch , contemptuous , disrespectful , flippant , impolite , offensive , shameless , supercilious , toplofty , unmannerly , wise