Illocutionary act is a term in linguistics introduced by the philosopher John L. Austin in his investigation of the
various aspects of speech acts. We may sum up Austin's terminology with the following example. In uttering the
locution "Is there any salt?" at the dinner table, one may thereby perform the illocutionary act of requesting salt, as
well as the distinct locutionary act of uttering the interrogatory sentence about the presence of salt, and the further
perlocutionary act of causing somebody to hand one the salt.
The notion of an illocutionary act is closely connected with Austin's doctrine of the so-called ‘performative’ and
‘constative utterances': an utterance is "performative" if, and only if it is issued in the course of the "doing of an
action" (Austin, 1955), by which, again, Austin means the performance of an illocutionary act (Austin, 1955).
According to Austin's (1962) original exposition in How to Do Things With Words, an illocutionary act is an act (1)
for the performance of which I must make it clear to some other person that the act is performed (Austin speaks of
the 'securing of uptake'), and (2) the performance of which involves the production of what Austin calls 'conventional
consequences' as, e.g., rights, commitments, or obligations (Austin, 1955) Thus, for example, in order to make a
promise I must make clear to my audience that the act I am performing is the making of a promise, and in the
performance of the act I will be undertaking an obligation to do the promised thing: so promising is an illocutionary
act in the present sense. Since Austin's death, the term has been defined differently by various authors.