In linguistics, a causative (abbreviated CAUS) is a valency-increasing operation that indicates that a subject causes someone or something else to do or be something, or causes a change in state of a non-volitional event. Prototypically, it brings in a new argument (the causer), A, into a transitive clause, with the original S becoming the O.
All languages have ways to express causation but differ in the means. Most, if not all, languages have lexical causative forms (such as English rise → raise, lie → lay, sit → set). Some languages also have morphological devices (such as inflection) that change verbs into their causative forms or adjectives into verbs of becoming. Other languages employ periphrasis, with control verbs, idiomatic expressions or auxiliary verbs. There tends to be a link between how "compact" a causative device is and its semantic meaning.
It is to be noted that the prototypical English causative verb or control verb used in periphrasis is make rather than cause. Linguistic terms are traditionally given names with a Romance root, which has led some to believe that cause is more prototypical. While cause is a causative, it carries some lexical meaning (it implies direct causation) and is less common than make. Also, while most other English causative verbs require a to complement clause (for example, "My mom caused me to eat broccoli"), make does not for example, "My mom made me eat broccoli") at least when it is not being used in the passive.
Many authors have written extensively on causative constructions and have used a variety of terms, often to talk about the same things.
S, A, and O are terms used in morphosyntactic alignment to describe arguments in a sentence. The subject of an intransitive verb is S, the agent of a transitive verb is A, and the object of a transitive is O. Note that these terms are technically not abbreviations (anymore) for "subject", "agent", and "object", though they can usually be thought of that way. Note that P is often used instead of O in many works.