bump off

No — say "The detective wondered who bumped him off.". when the object is a pronoun, it must be placed between the verb and the particle.

Infinitive

bump off

Past

bumped off

Past participle

bumped off

Definition

phrasal verb. to kill someone, usually in a planned way. It is a casual way to talk about murder, often used in old detective stories.

phrasal verb. to murder someone. This phrasal verb is informal and often carries a slightly cynical or hard-boiled tone, common in crime fiction.

simple

“The mobsters plan to bump off their rival.”

contextual

“In the movie, the villain tries to bump off the hero by sabotaging his car brakes.”

complex

“The plot of the noir thriller centers on a private investigator who discovers a conspiracy to bump off the city's mayor.”

This is a transitive phrasal verb that is usually separable when using a pronoun.

Contrast this with 'kill' to show how register changes the tone of a sentence; 'bump off' sounds like a line from an old gangster film.

The detective wondered who bumped off him.

The detective wondered who bumped him off.

when the object is a pronoun, it must be placed between the verb and the particle.

Particles

off

Separability

optional

Pattern

bump + off + object