1. Expressions (phrases, clauses, etc.), Noun

   good thing; nice thing

   Usually written using kana alone

2. good excuse; good grounds; good opportunity

   Usually written using kana aloneusu. as 〜をいいことに(して)

3. (good) idea

   Usually written using kana aloneChildren's language

4. Interjection (kandoushi)

   interjection used to impress an idea or to urge a response

   Female term or languageUsually written using kana alone

Also written 好い事【いいこと】iikoto、善い事【いいこと】iikoto