1.to make someone disappointed by not doing something that they are expecting you to do; to work less hard or make more mistakes than the people who you are working with
2.to make someone or something less likely to be successful or effective
3.to allow the air to go out of something such as a car tire
4.to allow someone or something to move to a lower position
5.to use the extra cloth in the hembottom fold of a piece of clothing to make it longer
6.to try to give someone bad news in a way that does not upset them too much
7.to work less hard or to make more mistakes than the people who you are working with
lets down