(いちいち)

いちいち
adverb
one by one; every single
descriptive
1. one by one; individually; every single
Doing something for each item or instance separately, often with a nuance of it being tedious or unnecessary.
一々(いちいち)確認(かくにん)する
I check each one individually.
一々(いちいち)説明(せつめい)しなくてわかる。
I understand without having to explain every single thing.
そんなこと一々(いちいち)()にしないで。
Don't worry about every little thing like that.

一々(いちいち) often carries a negative nuance of being tedious or excessive.

Common patterns

Usage

When used critically, it suggests that someone is being overly meticulous or bothering with unnecessary details. In neutral usage, it simply means doing something item by item.