Specifically refers to an echo reverberating among mountains. In everyday contexts, こだま or エコー are more common for echoes in general.
谷に向かって叫ぶと、山彦が返ってきた。
When I shouted toward the valley, an echo came back.
mountain god; mountain guardian deity
A deity or spirit believed to dwell in mountains and cause echoes. This sense is mythological and rarely used in modern conversation outside folklore contexts.
昔話では、山彦は山の神として描かれることがある。
In old tales, yamabiko is sometimes depicted as a mountain deity.
Standard kanji spelling for both the echo and the deity sense.
Mixed kanji-kana spelling; easier to read and sometimes used in children's materials or when the kanji 彦 is considered difficult.
Compound of 山 (yama, 'mountain') and 彦 (hiko, 'boy' or 'prince'), originally referring to a mountain spirit whose voice was thought to be the echo. The exact historical derivation is uncertain.