underbrag UK /ˌʌn.dəˈbɹæɡ/US /ˌʌn.dɚˈbɹæɡ/ noun1 •(rare) A confident statement involving openly acknowledging shortcomings, demonstrating indifference to others' opinions.The underbrag is social media's recent, cheeky response to the slightly less recent humblebrag,[…] — 2017 formsunderbrags