Butter wouldn't melt in his mouth

Definitions

• someone is pretending to be innocent or harmless
  To describe someone who is acting or speaking in a way that suggests they are innocent, sweet, or harmless, but in reality they are not and are likely up to no good.

• someone is being insincere or deceitful
  To imply that someone is being dishonest or insincere in their actions or words, often in a manipulative or scheming way.

Examples of Butter wouldn't melt in his mouth

Conclusion

This idiom is used to describe someone who is putting on a facade of innocence or harmlessness, but is actually being insincere or deceitful. It can be used to caution against trusting someone who may have ulterior motives or to sarcastically point out someone's dishonesty.

Origin of "Butter wouldn't melt in his mouth"

The origin of this idiom is believed to come from the 16th century play, "Gammer Gurton's Needle" by John Still. In the play, a character is described as "looking as meek as a lamb, that would not harm a fly, as mild as milk, as gentle as a dove, or the butter would not melt in her mouth." This phrase has evolved over time to become the common idiom we know today.

The use of butter in this idiom is likely due to its smooth and creamy texture, which gives the impression of something gentle and harmless. The phrase "wouldn't melt in his mouth" adds an extra layer of exaggeration, emphasizing the insincerity of the person being described.

This idiom is often used in a sarcastic or humorous way to poke fun at someone who is trying to appear innocent or harmless. It can also be used in a more serious manner to warn against trusting someone who may have hidden intentions. Overall, the origin of this idiom can be traced back to a play hundreds of years ago, but it has remained a common phrase in the English language, used to describe someone who is not as innocent as they may seem.