The kanji 基 generally conveys the idea of a foundation, base, or origin. It suggests something that supports or underlies something else, either physically or conceptually. It can also refer to a fundamental element or principle.

・On-yomi (音読み): キ ・Kun-yomi (訓読み): もと

⚫︎ 基本 (きほん) Translation: Basic; fundamental ⚫︎ 基礎 (きそ) Translation: Foundation; basis ⚫︎ 基地 (きち) Translation: Base (military or otherwise); base of operations

The kanji 基 is a phono-semantic compound (形声文字). It combines the phonetic component 其 (き - ki, meaning "its, that, them") and the semantic component 土 (つち - tsuchi, meaning "earth, ground"). The combination suggests something that provides a foundation or base, like the earth itself. The phonetic component also suggests the sound of the character.