behaving outrageously as though there were no one around; acting without consideration for others; arrogance; audacity; insolence
men and women of all ages
young person; inexperienced person; novice
inexperienced person; young person; novice; greenhorn
having presence of mind; self-possessed; imperturbable; calm and self-possessed
youngster; young and immature person
early-onset Alzheimer's disease
early-onset dementia; presenile dementia
(staring in) astonishment; amazement
to strike someone dumb with astonishment
early-onset dementia; presenile dementia
perfect composure; calm and collected
having presence of mind; imperturbable; calm and self-possessed; with serenity