Is "背中に嫌な汗を掻いた" an idiomatic phrase?


Okay I read a light novel and found a phrase that seems nonsensical to me.

The sentence is: "私を見ながら背中に嫌な汗を掻いた。" The context is that a character in the
story just realize something about the Main Character.

The phrase that confuse me is "背中に嫌な汗を掻いた。"

Is "getting your back wet with sweat" an idiomatic phrase in Japanese? Does
that means he was fear or afraid?

What does it really mean? I try to search the dictionary that I have but I
don't find the relevant meaning.




嫌な汗 is commonly used and refers to sweat that comes out in a "bad situation",
especially in anticipation of a "bad situation". In my personal opinion it
emphasizes how the person is still maintaining his/her composure (rather than
flailing around, screaming, running away etc.) despite being very worried or
distressed inside.

For example, if you are a fighter pilot and realize you don't have enough fuel
to get home, or you are walking in a sketchy part of town and you realize
sketchy figures are following you, or you are a sword master and you realize
the opponent is much stronger than you thought, etc.

背中に is just a choice by the author I think. You could equally say
顔に嫌な汗をかいた、but perhaps it serves to further emphasize how he/she is maintaining
composure (because if you are all sweaty on your face, it's easier to notice).




嫌な汗 is commonly used and refers to sweat that comes out in a "bad situation",
especially in anticipation of a "bad situation". In my personal opinion it
emphasizes how the person is still maintaining his/her composure (rather than
flailing around, screaming, running away etc.) despite being very worried or
distressed inside.

For example, if you are a fighter pilot and realize you don't have enough fuel
to get home, or you are walking in a sketchy part of town and you realize
sketchy figures are following you, or you are a sword master and you realize
the opponent is much stronger than you thought, etc.

背中に is just a choice by the author I think. You could equally say
顔に嫌な汗をかいた、but perhaps it serves to further emphasize how he/she is maintaining
composure (because if you are all sweaty on your face, it's easier to notice).

