In grammar, an intransitive verb is a verb, aside from an auxiliary verb, whose context does not entail a transitive object. That lack of an object distinguishes intransitive verbs from transitive verbs, which entail one or more objects. Additionally, intransitive verbs are typically considered within a class apart from modal verbs and defective verbs.

In the following sentences, verbs are used without a direct object:

The following sentences contain transitive verbs (they entail one or more objects):

Some verbs, called ambitransitive verbs, may entail objects but do not always require one. Such a verb may be used as intransitive in one sentence, and as transitive in another.

In general, intransitive verbs often involve weather terms, involuntary processes, states, bodily functions, motion, action processes, cognition, sensation, and emotion.

The valency of a verb is related to transitivity. Where the transitivity of a verb only considers the objects, the valency of a verb considers all the arguments that correspond to a verb, including both the subject of the verb and all of the objects.

It is possible to change the contextually indicated sense of a verb from transitive to intransitive, and in so doing to change the valency.

In languages that have a passive voice, a transitive verb in the active voice becomes intransitive in the passive voice. For example, consider the following sentence: