Translation guide
Describes a person who is obsessively focused on a single topic or goal, often to the exclusion of everything else. In Japanese, this is expressed through idioms, adjectives, and descriptive phrases rather than a single direct equivalent.
To describe someone who can only think about one topic, goal, or activity, often in a narrow-minded or single-minded way.
Literally 'can't turn one's head to anything but one thing'. A natural way to say someone has a one-track mind, unable to consider other things.
彼は仕事のことで一つのことにしか頭が回らない。
He has a one-track mind when it comes to work.
To describe someone whose mind is constantly on sexual matters, a common connotation of 'one-track mind' in English.
Colloquial and direct: 'head full of erotic thoughts'. Equivalent to 'one-track mind' in a sexual sense.
あいつはいつも頭の中がエロでいっぱいだ。
That guy always has a one-track mind.
There is no direct Japanese equivalent for 'one-track mind'. Translating it word-for-word (e.g., 一線の心) would be meaningless. Use the phrases above depending on context.
一本気 can be positive (dedicated, straightforward) or negative (stubborn, narrow). 視野が狭い is always negative, implying a lack of broader perspective. Choose based on whether you want to criticize or simply describe.
Describes a person who is single-minded, straightforward, and devoted to one thing. Can be positive (dedicated) or negative (narrow-minded) depending on context.
彼は一本気な性格で、趣味に没頭している。
He has a one-track mind and is absorbed in his hobby.
Means 'narrow-minded' or 'having a narrow perspective'. Often used when someone can't see beyond their own interests or ideas.
彼は自分の意見に固執して、視野が狭くなっている。
He's so fixated on his own opinion that he's developed a one-track mind.
Literally 'single-point concentration type'. A somewhat technical or business-like term for someone who focuses intensely on one thing.
彼は一点集中型で、他のことが目に入らない。
He's the one-track mind type; nothing else gets his attention.
Means 'only thinking about lewd things'. A blunt, informal way to say someone has a one-track mind for sex.
彼はスケベなことしか考えていないんだ。
He's got a one-track mind, only thinking about sex.
Literally 'think with one's lower body'. A euphemistic but vivid expression for being driven by sexual desire.
彼は下半身でものを考えているとしか思えない。
I can only think he has a one-track mind.