Semantic shifting goes by many different names. In his pioneering article, Benedict 1939 calls it "semantic differentiation." In his article on Gnau,… - James Alan Matisoff

In the Beginning was the Sino-Tibetan monosyllable, arrayed in its full consonantal and vocalic splendor. And the syllable was without tone and devoid of pitch. And monotony was on the face of the mora. And the Spirit of Change hovered over the segments flanking the syllabic nucleus.
And Change said, "Let the consonants guarding the vowel to the left and the right contribute some of their phonetic features to the vowel in the name of selfless intersegmental love, even if the consonants thereby be themselves diminished and lose some of their own substance. For their decay or loss will be the sacrifice through which Tone will be brought into the world, that linguists in some future time may rejoice."
And it was so. And the Language saw that it was good, and gradually began to exploit tonal differences for distinguishing utterances – yea, even bending them to morphological ends. And the tones were fruitful and multiplied, and diffused from tongue to tongue in the Babel of Southeast Asia.

The South-East Asian mono-syllable often seems to be bulging at the seams with phonetic material: consonantal, vocalic, and supra-segmental.

All this having been said, if I were to pick a single word to describe [Joseph] Greenberg's apparent motivation in doing megalocomparison, it would have to be columbicubiculomania-a compulsion to stick things into pigeonholes, to leave nothing unclassified. Greenberg gives the impression that the highest intellectual activity is the act of classification itself, regardless of the nature of the evidence upon which the classification rests.