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

See Examples For:

let down

"Thames Water customers have been let down for far too long, with 15 years of under-performance, increasing serious pollution, and customers left to pick up the bill," the spokesperson said.

From BBC ● Jul. 19, 2026

"Pupils, parents and schools have been badly let down," he said.

From BBC ● Jul. 2, 2026

"People have heard this sort of talk before only to be badly let down because nothing changes – Burnham mustn't repeat that mistake," he said.

From BBC ● Jun. 29, 2026

Sarah Hawkins - Harriet's mother and a whistleblower of the maternity scandal - said she felt let down by those who cared for her.

From BBC ● Jun. 24, 2026

I had forgotten to draw my curtain, which I usually did, and also to let down my window-blind.

From "Jane Eyre" by Charlotte Brontë