幌泉 ほろいずみ Horoizumi
Erimo, Hidaka region, Hokkaidō
Ainu spellings: Poro-entum
The two readings differ over one consonant and over which landform the name names, the cape 20 km away or the bluff above the town.
Location
42.0337, 143.1792 · Coordinates: OpenStreetMap Nominatim, 2026-09-10, on 幌泉川. Open in OpenStreetMap
Referents
- settlement The seat of the Erimo town office, formerly Horoizumi village of Horoizumi county, renamed Erimo town in 1970. The bluff behind Erimo harbour, 55 m high, divides the town
Analyses
poro-enrum
ポロエンルム ‘big cape’ received readingProponent: 定説
The cape is taken to be Cape Erimo.
Objections
- Horoizumi lies far from Cape Erimo and no account tells of Ainu being moved there from Erimo. A change from Horoenrum to Horoizumi is forced. — zenibako_trek zenibako_trek…
Both parts are dictionary words; the objection is to the distance between the name and the cape and to the sound change required.
poro-entum
ポロエントゥム ‘big cliff face’ proposedProponent: zenibako_trek（小樽銭函地名歴史研究会） (zenibako_trek (Otaru Zenibako Place-Name and History Society))
tom or tum is said to name the middle of a face such as a cliff wall, a surface one can meet or run into head on. On that reading en-tum is a protruding cliff face and Horoizumi is the big one, the bluff that rises behind Erimo harbour. The author holds that the change to Horoizumi is then unforced. He reads Shiroizumi east of Urakawa the same way, sir-o-entum 'cliff face on the mountain'.
Evidence
- parallel place names
Names in enrum and in entomo occur across Hokkaidō, and the article separates them by landform: an enrum juts out conspicuously, an entomo hardly reads as a cape on a map. Etomo at Muroran belongs to the second group, and the author rejects reading it enrum.
poro and tum are dictionary items, tum as a locative noun for the middle of something, and the bluff behind the harbour is there. The sense of tum the reading needs, a cliff face met head on, is quoted in the article without a source, and the element en is the author's.