let down

British  

verb

1. (also preposition) to lower

2. to fail to fulfil the expectations of (a person); disappoint

3. to undo, shorten, and resew (the hem) so as to lengthen (a dress, skirt, etc)

4. to untie (long hair that is bound up) and allow to fall loose

5. to deflate

   to let down a tyre

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noun

1. a disappointment

2. the gliding descent of an aircraft in preparation for landing

3. the release of milk from the mammary glands following stimulation by the hormone oxytocin

let down Idioms  

1. Cause to descend, lower, as in They let down the sails . [Mid-1100s]

2. Also, let up . Slacken, abate, as in Sales are letting down in this quarter , or They didn't let up in their efforts until the end . The first term dates from the mid-1800s, the variant from the late 1700s.

3. See let someone down . Also see let one's hair down .

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Example Sentences

But they were let down after the robotaxi took a route to avoid highways that doubled the trip’s time.

From MarketWatch • Apr. 10, 2026

However, the Department for Education said students had been let down by "incompetence or abuse of the system".

From BBC • Apr. 8, 2026

“I feel sad and let down by her,” Sánchez said, referring to Dolores Huerta.

From Los Angeles Times • Mar. 19, 2026

From what you say, however, you were not only let down by the trustee of your mother’s estate, your attorney appears to have held you ransom to increasingly outrageous demands.

From MarketWatch • Mar. 11, 2026

So I kept working all day and felt let down when I came home with only four Zim dollars.

From "I Will Always Write Back" by Caitlin Alifirenka and Martin Ganda