[ mahynd-bog-ling ]
/ ˈmaɪndˌbɒg lɪŋ /
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adjective Slang.
intellectually overwhelming: a mind-boggling puzzle.
emotionally or psychologically overwhelming; mind-blowing.
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Origin of mind-boggling

First recorded in 1960–65

OTHER WORDS FROM mind-boggling

mind-bog·gling·ly, adverb
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023


What does mind-boggling mean?

Mind-boggling means utterly overwhelming to the mind or extremely difficult to understand or comprehend.

The verb boggle means to overwhelm or bewilder, such as with complexity or abnormality.

Things are often described as mind-boggling when they’re incredibly complex or exist on a scale that’s impossible to comprehend or “wrap your head around.”

A similar term is mind-blowing. Mind-blowing is usually used to describe things that are impressive, whereas mind-boggling usually describes things that are confusing or hard to even think about. Still, the terms are often used interchangeably.

The related verb phrase boggle the mind means to astound or be incomprehensible, as in His behavior really boggles the mind sometimes—I can’t begin to understand his motivation for doing the things he does.  

Example: The size and scale of the universe is mind-boggling—it’s impossible to grasp its magnitude.

Where does mind-boggling come from?

The first records of the term mind-boggling come from the mid-1900s. The phrase the mind boggles (at something) is recorded earlier, right around 1900. It’s basically the passive form of boggle the mind, as in The mind boggles at the unexplored depths of the ocean. The verb boggle may derive from the word bogle, an old term for a kind of ghost or goblin (the word boogeyman is based on the same root).

Things described as mind-boggling are incomprehensible, astounding, and bewildering. They overwhelm our minds with their utter complexity, massiveness, strangeness, or a combination of these things. Of course, the word is often used to exaggerate how big or complex something is. Big numbers are often described as mind-boggling. Another word for this is astronomical, as in The estimated cost is astronomical—it’s mind-bogglingly huge. This uses the scale of the universe as a metaphor for things that are huge and unable to be put in perspective. This is exactly the kind of thing that mind-boggling is used to describe.

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What are some other forms related to mind-boggling?

  • mind-bogglingly (adverb)

What are some synonyms for mind-boggling?

What are some words that share a root or word element with mind-boggling

What are some words that often get used in discussing mind-boggling?

How is mind-boggling used in real life?

Mind-boggling is typically used informally, even when applied to scientific topics like the size of the universe.



Try using mind-boggling!

Is mind-boggling used correctly in the following sentence?

The fact that such a bad movie can win so many awards is mind-boggling.

How to use mind-boggling in a sentence

British Dictionary definitions for mind-boggling


informal astonishing; bewildering
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012