KanjiJLPT N4
Inside

inside, within, between, among, house, home

Mnemonic

A person crawls through a dark tunnel, feeling the walls close in around them. The tunnel is warm, fleshy, pulsing—the person gasps, realizing they're inside the belly of a wale.
Additional thoughts
Picture the kanji 内 itself: the outer strokes form the tunnel entrance, and the inner stroke is the person swallowed within. The claustrophobic, living warmth reinforces the sense of being enclosed inside something.
Quick recall
A person trapped in a fleshy tunnel realizes they're inside the belly of a wale.

Details

The keyword for 内 is inside. This kanji represents the concept of being within, interior, or internal, as opposed to what is outside or external. It conveys the idea of something contained within a boundary or enclosure, whether referring to a physical space like the inside of a building or a more abstract sense such as being within a group, organization, or period of time. It is often used in contrast with 外 (outside) to distinguish between what is internal and what is external.
On'yomi
ない、だい
Kun'yomi
うち