'buoy up' definitions:

Definition of 'buoy up'

(from WordNet)
verb
Become more cheerful; "after a glass of wine, he lightened up a bit" [syn: lighten, lighten up, buoy up]
verb
Make more cheerful; "the conversation lightened me up a bit" [syn: lighten, lighten up, buoy up] [ant: weigh down, weigh on]
verb
Keep afloat; "The life vest buoyed him up" [syn: buoy, buoy up]