We found one dictionary that defines the word be good at:

Phrases: Be Good to Yourself at Least Once a Day, to be good at something, be good at something, to be good at, a job one would be good at, more... ▸ Words similar to be good at ▸ Usage examples for be good at ▸ Idioms related to be good at ▸ Wikipedia articles (New!) ▸ Words that often appear near be good at ▸ Rhymes of be good at ▸ Invented words related to be good at