From Wiktionary, the free dictionary
*-rə element, appears to be noun forming suffix indicating a general area/place, compare *təkərə (“place”).
*osirə
- back, behind
- Eastern Old Japanese:
- Old Japanese: うしろ (usiro1, usiro2)
- Proto-Ryukyuan: *usiro
- Northern Ryukyuan:
- Okinawan:
- Shuri: 後 (ushiru, “nape of neck”) (tone class BC)
- Okinoerabu:
- Kamihirakawa: 後 (ushu)
- Kunigami: 後 (ushu)
- Tamina: 後 (ushū)
- Southern Amami Ōshima:
- Shodon: 後 (ushryo)
- Yoron:
- Mugiya: 後 (ussū)
- Southern Ryukyuan:
- Miyako:
- Hirara: 後 (ussu)
- Minna: 後頭部 (usshu, “occiput”) (tone class C)
- Yaeyama:
- Aragusuku: 後頭部 (ussōn) (< *usirogami (“occiput”))
- Hateruma: 後頭部 (ussu), 後頭部 (usson) (< *usirogami (“occiput”))
- Ishigaki: 後頭部 (uson) (< *usirogami (“occiput”))
- Kuroshima: 後頭部 (uson) (< *usirogami (“occiput”))
- Taketomi: 後頭部 (ushon) (< *usirogami (“occiput”))
- Yonaguni: 後頭部 (usungai) (< *usirogami (“occiput”))