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

Stephen Spiers was a member of Whitewell Metropolitan Tabernacle for more than 30 years, but said he felt "so let down" by how the church acted when concerns were brought forward.

From BBC • Apr. 10, 2026

Mr Foreman said the couple, who were arrested in January 2025 while on a global motorbike journey, felt "let down, alone and completely frustrated".

From BBC • Mar. 23, 2026

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

From Los Angeles Times • Mar. 19, 2026

The bell rang three times, announcing that we were about to be let down.

From "October Sky" by Homer Hickam