故意 (koi) means “intent” | MotiTan Japanese Dictionary

More examples

警察は事故ではなく故意の可能性も調べています。kei satsu wa ji ko de wa na ku ko i no ka nō sei mo shira be te i ma su

The police are also investigating the possibility that it was intentional rather than an accident.

Describes an intention that leads to an action done deliberately rather than by accident.

意図ito: The purpose that a person has in mind when taking an action.
意思ishi: A person's deliberate choice or wish to carry out an action.

偶然ではなく、ある行為をわざと行おうとする意図。gū zen de wa na ku a ru kō i o wa za to okona ō to su ru i to

故意 (koi) combines 故 (ko, "intentionally") and 意 (i, "intention"), so the compound denotes an intention to act deliberately.

In courtroom language, 故意 (koi) identifies a person's deliberate state of mind, so it concerns what the person meant to do rather than only what happened.