puffing up
phrasal verbUK /ˈpʌfɪŋ ʌp/
US /ˈpʌfɪŋ ʌp/
Making something get bigger by filling it with air.
The bird was puffing up its feathers to stay warm.
OTHER MEANINGS
2. Making someone feel too proud or important about themselves.
All the praise was puffing him up too much.
3. Breathing hard and fast after running or exercise.
She was puffing up after climbing all those stairs.
4. Making something look bigger or better than it really is.
The ad was puffing up the toy's abilities.