Translation guide
The English word 'spy' can be a noun (a person who secretly collects information) or a verb (to secretly observe or gather information). In Japanese, different words and expressions are used depending on the context, such as espionage, casual snooping, or noticing something.
Referring to a professional or amateur person engaged in espionage, often for a government or organization.
The most common and direct translation, used for both professional spies and in casual contexts. A loanword from English.
彼は敵国のスパイだった。
He was a spy for the enemy country.
A formal or literary term for a spy, often used in historical or military contexts.
彼は間諜として敵地に潜入した。
He infiltrated enemy territory as a spy.
A secret agent or detective, often used in historical or fictional settings. Less common in modern everyday speech.
密偵が城の周りをうろついていた。
A spy was lurking around the castle.
The action of spying, either professionally or casually, such as snooping or eavesdropping.
Literally 'to do spy activities'. A natural way to express engaging in espionage.
彼は長年、スパイ活動をしていた。
He had been engaged in spying for many years.
To probe, investigate, or spy on someone/something. Commonly used for both physical searching and information gathering.
敵の動きを探っている。
We are spying on the enemy's movements.
彼は私の秘密を探ろうとした。
He tried to spy on my secrets.
To scout or reconnoiter, often used in military contexts or for observing an area.
兵士が敵陣を偵察した。
The soldiers spied on the enemy camp.
To peek or look into, often used for casually spying on someone or snooping. Can imply a quick or secretive glance.
To steal a glance or secretly watch. Emphasizes the secretive nature of the act.
Using 'spy' in the sense of spotting or glimpsing something, often from a distance or unexpectedly.
To find or spot something. The most natural way to express 'spy' when you suddenly see something.
遠くに船を見つけた。
I spied a ship in the distance.
To recognize or make out visually. Slightly more formal, often used in written language.
To spot something with a sharp eye. Emphasizes keen observation.
彼女は目ざとく隠しカメラを見つけた。
She spied the hidden camera with her sharp eyes.
When talking about casually snooping on someone (like checking their phone), using スパイする might sound too serious or like espionage. Instead, use 覗く (のぞく) or 探る (さぐる) for a more natural fit.
彼の携帯を覗いた。
I spied on his phone (peeked at it).
スパイ is a spy, usually working for a government or organization in secret. 探偵 is a detective, often a private investigator hired to gather information legally. Don't confuse them.
Don't spy on the next room.
彼女は手紙を盗み見た。
She spied on the letter (secretly read it).
彼は遠くに人影を認めた。
He spied a figure in the distance.