Centum
Centum is the collective name for the branches of
Indo-European in which the so-called
Satem shift, the change of palato-
velar *k
^, *g
^, *g
^h into fricatives or affricates, did not take place, and the palato-velar consonants merged with plain velars (*k, *g, *g
h). Most of the Centum languages preserve Proto-Indo-European labio-velars (*k
w, *g
w, *g
wh) or their historical reflexeses as distinct from plain velars; for example,
PIE *k, *k
w >
Latin c /k/,
qu /k
w/,
Greek /k/, /p/ (or /t/ before front vowels),
Gothic /h/, /h
w/, etc.
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.
The Centum branches include Anatolian, Tocharian, Italic, Celtic, Germanic, Greek, and probably a number of minor and little known extinct groups.
The Centum group is a paraphyletic group and thus not a phylogenetic unit.