lost in thought

Save This Word!

Concentrating on or pondering over something. For example, Gwen didn't hear a word you said; she was lost in thought.

Should you take this quiz on “shall” versus “should”? It should prove to be a quick challenge!
Question 1 of 6
Which form is used to state an obligation or duty someone has?
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.


What does lost in thought mean?

Lost in thought is a phrase that means to be thinking about something really hard, as in Ben was lost in thought as he considered his options. 

Often, the phrase lost in thought is used to describe someone who is concentrating so hard on their own thoughts that they lose track of their surroundings, as in or I didn’t hear the phone ring because I was so lost in thought.

Example: I was so lost in thought as I strolled down the street that I accidentally walked into a stop sign.

Where does lost in thought come from?

The first records of the phrase lost in thought come from around 1681. It combines the words lost, in the sense of preoccupied or engrossed by something, and thought, meaning mental activity or the forming of ideas. When you are lost in thought, you are so focused on your own thoughts that you have become figuratively lost and aren’t paying attention to anything else.

You don’t have to be thinking about important things, like what career you would be suited for, to be lost in thought. You can be lost in thought about ordinary things, like what to have for lunch. (We like pizza for lunch.)

Did you know … ?

What are some synonyms for lost in thought?

What are some words that share a root or word element with lost in thought

What are some words that often get used in discussing lost in thought?

How is lost in thought used in real life?

Lost in thought is a common phrase used to describe a person who is completely absorbed by their own pondering.

Try using lost in thought!

Is lost in thought used correctly in the following sentence?

Trying to decide which city to visit next, Nicole was lost in thought as she sat at the counter.

How to use lost in thought in a sentence