磐

Literal: A large rock or boulder, specifically a flat-topped stone, slab, or plinth capable of supporting weight (e.g., an altar or foundation).

Metaphorical: Firmness, stability, and immovability. When applied to abstract concepts—such as resolve or the heart—it denotes a state of being anchored or steadfast.

Noun: Used for the physical object (slab/boulder).

Attributive Modifier: Used to describe a quality of being "firm" or "immovable."

vs. 石 (shí): While 石 is the generic term for stone, 磐 specifies scale and shape as massive and broad.

vs. 岩 (yán): Where 岩 typically suggests a cliff, crag, or precipice, 磐 emphasizes a flat expanse or a grounded base.

The relationship to the phonetic component 盤 (tray/plate) reinforces the semantic nuance of a broad, flat surface.