Translation guide
The English word "concentration" covers several distinct meanings: mental focus, the amount of a substance in a mixture, and the act of gathering or bringing together. This guide helps learners choose the right Japanese expression for each meaning.
The ability to direct one's attention or mental effort on a single task or thought.
The most common and general word for mental concentration. Used as a noun or in the verb 集中する (to concentrate).
試験中は集中が切れた。
I lost concentration during the exam.
集中力が足りない。
I lack concentration.
Implies being absorbed or immersed in something, often with a positive nuance of deep engagement. Used as 没頭する.
彼は研究に没頭している。
He is absorbed in his research.
Focusing exclusively on one thing, often with a sense of dedication. Used as 専念する.
勉強に専念したい。
I want to concentrate on my studies.
A formal, literary term for devoting one's energy or attention to something. Often used in written language.
彼はその問題に全力を傾注した。
He concentrated all his energy on the problem.
The measure of how much of a given substance is present in a solution or mixture, often expressed as a percentage or ratio.
The standard term for concentration in scientific contexts (chemistry, biology, etc.).
この溶液の濃度を測ってください。
Please measure the concentration of this solution.
アルコール濃度が高い。
The alcohol concentration is high.
Refers to the amount or content of a specific substance contained in something, often used in nutrition or material composition.
The act of collecting or bringing people or things together in one place.
Also used for the gathering of things or people in one place, especially in phrases like 人口集中 (population concentration).
人口が都市に集中している。
The population is concentrated in cities.
Often used for troops, forces, or large groups assembling. Can be used as 集結する.
Similar to 集結, but often implies rallying or mustering strength, efforts, or people for a purpose.
集中 is the most general and neutral term for concentration. 没頭 implies being so absorbed that you lose track of surroundings, often with a positive, passionate nuance. 専念 suggests dedicating yourself exclusively to one task, often with a sense of purpose or duty.
While 集中 can mean gathering, it is not used for the concentration of a substance in a solution. Use 濃度 instead.
塩分の濃度
salt concentration
While 集中 can mean gathering, it is not used for the concentration of a substance in a solution. Use 濃度 instead.
塩分の濃度
salt concentration
この食品の塩分含有量は少ない。
The salt concentration in this food is low.
軍隊が国境に集結した。
Troops concentrated at the border.
力を結集して問題に当たる。
We will concentrate our efforts to tackle the problem.