(じこ)

じこ
noun
self; oneself; the self
1. the self; one's own person; oneself (as an abstract concept)
A formal, written word for "the self" as an abstract concept, or as the first element of compound nouns such as 自己(じこ)紹介(しょうかい) (self-introduction) and 自己(じこ)評価(ひょうか) (self-evaluation). Rarely used alone in ordinary conversation — speakers prefer 自分(じぶん) when referring to themselves concretely.
自己(じこ)紹介(しょうかい)をしてください。
Please introduce yourself.
自己(じこ)責任(せきにん)参加(さんか)してください。
Please participate at your own risk.
(かれ)自己(じこ)分析(ぶんせき)得意(とくい)で、自分(じぶん)長所(ちょうしょ)短所(たんしょ)をよく理解(りかい)している。
He is good at self-analysis and understands his strengths and weaknesses well.
就職(しゅうしょく)面接(めんせつ)では、自己(じこ)PR(ピーアール)時間(じかん)(かなら)(もう)けられている。
In job interviews, there is always time set aside for self-promotion.

A formal, Sino-Japanese word for "the self." In modern Japanese, 自己(じこ) is rarely used as a standalone pronoun — speakers say 自分(じぶん) in conversation. Its main role is as the first element of a large family of compound nouns from psychology, business, law, and self-help writing.

COMMON COMPOUNDS (extremely productive):

  • 自己(じこ)紹介(しょうかい): self-introduction
  • 自己(じこ)責任(せきにん): personal responsibility; at one's own risk
  • 自己(じこ)評価(ひょうか): self-evaluation
  • 自己(じこ)分析(ぶんせき): self-analysis
  • 自己(じこ)主張(しゅちょう): self-assertion
  • 自己(じこ)満足(まんぞく): self-satisfaction; complacency (often negative)
  • 自己(じこ)中心的(ちゅうしんてき): self-centered
  • 自己(じこ)嫌悪(けんお): self-loathing
  • 自己(じこ)実現(じつげん): self-actualization; self-realization
  • 自己(じこ)(りゅう): one's own style; self-taught way
  • 自己(じこ)PR: self-promotion (job interviews)

SIMILAR WORDS:

  • 自分(じぶん): oneself; myself — the ordinary, conversational word; used as a pronoun and in everyday speech.
  • 自己(じこ): the self — written/abstract; used almost exclusively in compounds and formal writing.
  • 本人(ほんにん): the person themselves; in person — used to distinguish a person from a proxy or representative.
  • (われ): I; self — literary and philosophical.

USAGE WARNING:
Do not use 自己(じこ) in place of 自分(じぶん) in normal sentences. Saying 自己(じこ)学生(がくせい)です is unnatural — say 自分(じぶん)学生(がくせい)です (or simply (わたし)学生(がくせい)です).

自己(じこ) is best thought of as a stem for building abstract compounds rather than a pronoun.