v. phr. 1. To allow to descend; lower. Harry let the chain saw down on a rope and then climbed down himself. 2. To relax; stop trying so hard; take it easy. The horse let down near the end of the race and lost. The team let down in the fourth quarter because they were far ahead.
Compare: LET GO. 3. To fail to do as well as (someone) expected; disappoint. The team felt they had let the coach down.