常磐

⟨to₂ko₂ ipa⟩ → ⟨to₂ki₁pa⟩ → */təkʲipa/ → /tokifa/ → /tokiwa/

From Old Japanese.

Shift from a compound of 常 (toko, “unchanging”) +‎ 岩 (iwa, “rock”).^[1][2]

The evergreen sense is ateji for 常葉 (tokiwa, tokoha, literally “eternal + leaves”).

• 常盤

• (Tokyo) ときわ (Heiban – )^[2]
• IPA^(key):

常(とき)磐(わ) • (tokiwa) ^{←ときは (tokifa)?}

1. (literal) a rock that does not change over time
2. (figurative) eternity
3. 常葉: an evergreen tree

常(とき)磐(わ) • (tokiwa) ^{←ときは (tokifa)?†}-nari

1. (archaic) eternal, unchanging
2. (archaic) evergreen

常(とき)磐(わ) • (Tokiwa) ^{←ときは (Tokifa)?}

1. a place name
2. a surname
3. a female given name

/d͡ʑauban/ → /d͡ʑɔːban/ → /d͡ʑoːban/

From the first kanji of the names of the provinces: the 常 (jō) of 常陸 (Hitachi), and the 磐 (ban) of 磐城 (Iwaki).

• IPA^(key):

常(じょう)磐(ばん) • (Jōban) ^{←じやうばん (Zyauban)?}

1. (historical) the provinces of Hitachi and Iwaki
2. Jōban (a former city in southeastern Fukushima Prefecture, today merged with the city of Iwaki).
3. a surname