from The American Heritage® Dictionary of the English Language, 4th Edition
- n. A vowel change, characteristic of Indo-European languages, that accompanies a change in grammatical function; for example, i, a, u in sing, sang, sung. Also called gradation.
from the GNU version of the Collaborative International Dictionary of English
- n. The substitution of one root vowel for another, thus indicating a corresponding modification of use or meaning; vowel permutation; as, get, gat, got; sing, song; hang, hung.
from The Century Dictionary and Cyclopedia
- n. In philology, a substitution of one vowel for another in the body of the root of a word, accompanying a modification of use or meaning: as, bind, band, bound, bond, German bund; more especially, the change of a vowel to indicate tense-change in strong verbs, instead of the addition of a syllable (-ed), as in weak verbs: as, get, gat, got; sink, sank, sunk.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. a vowel whose quality or length is changed to indicate linguistic distinctions (such as sing sang sung song)
They exhibit perfectly the features of quantitative ablaut, which is the older form.
I doubt ablaut was still a productive system at the time that one could speak of 'Greek'.
Hittite and Greek do show words with ablaut. βλιττω is difficult to explain any differently.
No ablaut in a Greek noun can not be used as evidence that it isn't Indo-European.
I'm sure this wasn't the implication of what you were trying to say, as you must be aware that root-ablaut in Greek is non-existent in Greek.
"Hittite and Greek do show words with ablaut. βλιττω is difficult to explain any differently."
And ablaut in the root of consonant stems is unheard of in any form of Greek.
'Some words of this root in some languages have zero grade so it must be from the Genitive with ablaut.'
While the word is still clearly of foreign origin it is no surprised that we have no ablaut in the root.
"No ablaut in a Greek noun can not be used as evidence that it isn't Indo-European."