Among the six basic functions of language (referential, expressive [alternately called “emotive” or “affective”], conative, poetic, phatic, and metalinguistic [or “metalingual”]), according to which the act of verbal communication can be qualified, the last-named function is meant to describe the use of language to comment on itself, as when a word is defined in speech. The impetus for speakers to implement this self-referential function varies with their Sprachgefühl (a sensitivity to language, especially for what is grammatically or idiomatically acceptable in a given language), some possessing it in greater measure than others.
The incidence of free variation in language may provide the opportunity for the metalinguistic function to be utilized on any given occasion. This was in fact manifested today within Y-H-B’s hearing when his interlocutor (a male native speaker of American English in his twenties, with a college education) first pronounced the word data to rhyme with platter and then corrected himself by pronouncing it to rhyme with pater within the span of the same sentence. For the speaker in this viva voce example, this phonetic change evidently comported a higher self-valuation of the second variant over the first and may have been prompted by a latent orthoepic sense that was externalized by the felt linguistic requirements of the social situation, wherein the speaker’s interlocutor was also his intellectual superior.