Centum
Centum is the collective name for the branches of Indo-European (see: Indo-European languages) in which the so-called Satem shift (the change of palato-velar *k^, *g^, *g^h into fricatives or affricates; see: affricate) did not take place, and the palato-velar consonants merged with plain velars (*k, *g, *gh). Most of the Centum languages preserve Proto-Indo-European labio-velars (*kw, *gw, *gwh) or their historical reflexes as distinct from plain velars; for example, PIE *k, *kw > Latin c /k/, qu /kw/, Greek /p/t/ before front vowels), Gothic /hw The name Centum comes from the Latin word centum '100', pronounced [kentum] < PIE *k^mtom, illustrating the falling together of *k and *k^. Compare Sanskrit s′ata- or Russian sto, in which *k^ changed into a fricative (see: Satem).The Centum branches (which, by the way, developed independently from Proto-Indo-European and do not constitute a valid genetic unit) include Anatolian, Tocharian, Italic, Celtic, Germanic, Greek, and probably a number of minor and little known extinct groups.
