What does ひとりでに mean?
ひとりでに is a Japanese adverb meaning “by itself, automatically” in English. It is written as ひとりでに in hiragana, and hitorideni in romaji. This word is part of JLPT N2 vocabulary.
Example sentence
ろうそくはひとりでに消えた。
The candle went out of itself.