let down

Verb

let down (third-person singular simple present lets down, present participle letting down, simple past and past participle let down)

1. (idiomatic, transitive) To disappoint; to betray or fail somebody.
   • I promised him I would meet him there, and I will not let him down.
   • Just as they left, the younger of the two turned around and said, "Mr. President, I just want you to know that we're praying for you," and quickly closed the door behind him.
     I thought about these two men, and about the office workers that afternoon, and about the millions of others like them all...1978, Richard Nixon, “The Presidency 1973–1974”, in RN: the Memoirs of Richard Nixon, Grosset & Dunlap, →ISBN, →LCCN, →OCLC, →OL, page 1065

   Synonyms:

   cross up, dingo, sell out, stab in the back, assfuck, betray, burn, cop out, cross out, double-cross

   Antonyms:

   come through, keep faith, abide by, hold on, go to the wall for someone, stand by, stick by, stick with

2. (transitive) To lengthen by undoing and resewing a hem.

   Antonyms:

   take in

3. (intransitive) To reduce one's level of effort.
4. To soften in tempering.
   • to let down tools or cutlery
5. To thin; to reduce the thickness or viscosity of.
   • let the sauce down with a little pasta water if it starts to become too thick; if the soup is too thick, you can let it down with a little milk; let the sauce down with a dash of the pickling liquor; use some of the stock to let down the onion sauce
6. Used other than figuratively or idiomatically: see let, down: especially, to allow to descend.
   • let down your hair
   • let down a rope

   Antonyms:

   put up