Meaning
Describes a person with a prim, cool, innocent look or manner - originally just demure and proper, but now usually implying the innocence is feigned: someone who appears gentle or guileless while actually being sly, mischievous, or shrewder than they look. Typically framed as 'as if butter wouldn't melt in his mouth' and often shortened to 'butter wouldn't melt'. Informal and usually skeptical or teasing; the clipped form 'butter wouldn't melt' is common in attributive uses. Regional use: British English (also popular in the American South).
Origin
An old proverb. The earliest print record is John Palsgrave's French primer of 1530, and it appears in John Heywood's sixteenth-century proverb collections as 'She looketh as butter would not melt in her mouth' (dated 1546 by some references and 1562 by others). The image is of a mouth so cool and unmoved that butter would stay solid in it, building on 'cool' for calm detachment; Michael Quinion notes the phrase has been misunderstood - taken as a compliment about sweetness - for well over a century. The original sense was prim and proper with a cool demeanour; the now-dominant sense of deceptively demure developed from using it skeptically about someone whose meek look belied their character.
Research Sources
References used to check this entry’s meaning, history, or documented forms.
Variants
- a butter-wouldn't-melt expression
- as if butter wouldn't melt in your mouth
- butter wouldn't melt
- butter wouldn't melt in her mouth
- butter wouldn't melt in his mouth
Usage Examples
- The intern looked as if butter wouldn't melt in her mouth, yet she had reorganized the entire filing system over the weekend.
- He wears a butter-wouldn't-melt expression in meetings while quietly redirecting other people's work toward his own projects.
- The twins seemed as though butter wouldn't melt in their mouths when the neighbors came to ask about the broken window.