Japanese

Noun

紫陽花 ‎(hiragana あじさい, katakana アジサイ, romaji ajisai, historical hiragana あぢさゐ)

1. hydrangea

Etymology 2

Noun

紫陽花 ‎(hiragana しようか, katakana シヨウカ, romaji shiyōka, historical hiragana しやうくわ)

1. Same as above.

Usage notes

First reading is much more common. Like most flower names in Japanese, that reading uses Kanji for purely semantic purposes, without regards to pronunciation (a phenomenon known as Jukujikun. The characters translate literally to "purple (紫) sun (陽) flower (花)." The second reading is a true On'yomi version. Finally, because this a biological term, it is often spelled in Katakana.