root word: yabang

boastful, proud

Ang yabang mo naman.
My, you’re so boastful.

is being boastful

In Filipino culture, humility is considered virtuous. If for example you took a test in school and found it easy, then you honestly tell your friend that you found it easy, she will chastise you and say Ang yabang mo naman!

Statements that in American culture are considered neutral or factual may be considered pretentious or boasting by Filipinos.

boasting, bragging

ang kayabangan ng mga taong iyon
the boasting of those people

Slang: mahangin (“windy”)

When you feel that someone is being boastful, you can casually say out loud:

Ang hangin naman. 
My, it’s very windy.