一個(いっこ)

いっこ
noun, counter
one (object); one year (of age) difference
quantity
1. one (piece, item)
The number one when counting small objects or general items.
りんごを一個(いっこ)ください。
Please give me one apple.
一個(いっこ)100円(えん)で売(う)っている。
They're selling them for 100 yen each.
ここに一個(いっこ)だけ残(のこ)っていた。
There was only one left here.
2. one year difference (in age)
Used in casual speech to indicate age difference.
彼女(かのじょ)は一個(いっこ)上(うえ)だ。
She's one year older.
一個(いっこ)下(した)の後輩(こうはい)がいる。
I have a junior who's one year younger.
一個(いっこ)違(ちが)いなので気(き)が合(あ)う。
We get along because we're only one year apart.

Counting patterns

個(こ) is the general counter for small objects: 一個(いっこ), 二個(にこ), 三個(さんこ)… (卵(たまご)一個(いっこ), 一個(いっこ)ずつ one at a time, 一個(いっこ)100円(えん) 100 yen each).

Register

Sense 2 is casual, mainly among students and young people: 一個(いっこ)上(うえ) / 一個(いっこ)下(した) means one year above or below, usually one school year rather than exact age. In formal speech say 一(ひと)つ上(うえ) or 一歳(いっさい)年上(としうえ).

Related Words

Related: 〜個(こ) (counter for small objects)
Related: 一(ひと)つ (one (thing))
general
Added 2026.1.29 12:41 · Revised 2026.10.3 3:51
08500/08922_ikko