name of a Chinese river
沂 is a proper noun referring to a specific Chinese river. It has no general abstract meaning beyond this geographical name.
沂 combines 氵 (water) with 斤, which likely contributes the sound. It is a phono-semantic compound used as a river name.
The water radical 氵 beside 斤 suggests a river. Think of 斤 as a weight or axe marking the river's name: the River Yi.
For ギ, imagine a geyser erupting from the river: geyser -> ギ, and the water radical 氵 reinforces the river scene.
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