おはよう

Etymology
Originally a compound of, from adjective.

Modern Japanese -i adjectives formerly ended in -ki for the attributive form. This medial dropped out during the, both for the attributive form (-ki becoming -i) and for the adverbial form (-ku becoming -u). However, the adverbial form reverted back to -ku thereafter for most words, with the -u ending persisting in certain everyday set expressions, such as arigatō, ohayō, or omedetō, and in hyper-formal speech.

→ →

Interjection

 * 1) good morning

Usage notes
Most often written in hiragana. May occasionally be seen spelled in kanji, generally for more formal writing. Usually followed by in less casual contexts.