colloquial UK /kəˈləʊ.kwɪəl/US /kəˈloʊ.kwi.əl/adjective 2noun 1forms 2 adjective2 •Characteristic of familiar conversation, of common parlance; informal.You're using too many colloquial words in this cover letter: I suggest changing "I picked up loads of cool skills" to "I acquired many positive abilities"The colloquial, and at times sarcastic, tone of her books makes her popular with teenagers. •Of or pertaining to a conversation; conversational or chatty. noun1 •A colloquial word or phrase, colloquialism. formscolloquials · most colloquial