know-it-all

noun

ˈnō-ət-ˌȯl 

: one who claims to know everything

also : one who disdains advice

know-it-all adjective

Examples of know-it-all in a Sentence

Recent Examples on the Web

Predictably, this set off a furious round of acrimonious criticism, know-it-all navel-gazing, and schadenfreude. — Literary Hub, 9 Sep. 2026

Don Adams starred as bumbling know-it-all agent Maxwell Smart (Agent 86) opposite Barbara Feldon (Agent 99) and Edward Platt, who played the Chief. — Anthony D'alessandro, Deadline, 8 Sep. 2026

Bernstein was a know-it-all who was also a showoff, to put it bluntly, with both qualities neatly packaged as high style. — Adam Gopnik, New Yorker, 7 Sep. 2026

He will be joined by returning experts from the World Cup series, Elias Burke and Andy Jones, as well as Duncan Alexander, to form a rotating cast of Athletic know-it-alls. — The Athletic Soccer Experts, New York Times, 20 Aug. 2026

Word History

First Known Use

1873, in the meaning defined above

Rhymes for know-it-all

• aerosol
• alcohol
• arbitral
• basketball
• butanol
• cannonball
• carbinol
• cortisol
• ethanol
• fireball
• gasohol
• gossypol

Kids Definition

know-it-all

noun

ˈnō-ət-ˌȯl

: a person who always claims to know everything