Brainy (adjective)

1. Intelligent, having a high level of intelligence or mental ability.
2. Clever, having the ability to think quickly and make good decisions.

Origin:

From the word "brain".

Examples:

1. He was a brainy kid, always getting good grades and excelling in his studies.
2. She was known as the brainy one in the group, always coming up with clever solutions.
3. He was a brainy engineer, who could solve complex problems with ease.
4. She was a brainy scientist, who made many groundbreaking discoveries.
5. He was a brainy businessman, who could spot opportunities and take calculated risks.