A necessary commodity, a staple requirement.

"Rice is a basic for many Asian villagers."

An elementary building block, e.g. a fundamental piece of knowledge.

"Arithmetic is a basic for the study of mathematics."

Basic training.

"The drill sergeants gave him hell in basic."

Necessary, essential for life or some process.

"Flour is a basic ingredient of bread."

Elementary, simple, fundamental, merely functional.

"The Hotel Sparta’s accommodation is very basic."

Of or pertaining to a base; having a pH greater than 7.

Unremarkable or uninteresting; boring; uncool.