Grassmann's Law - in Greek

In Greek

In Koine Greek, outside of the context of reduplicating syllables, the alternations involving labials and velars have been completely levelled, and thus Grassmann's law only remains in effect for the alternation between /t/ and /tʰ/, as in the latter two examples above. It makes no difference whether the /tʰ/ in question continues PIE *dʰ or *ɡʷʰ-.

Thus alongside the pair 'fast' : 'faster' displaying Grassmann's law, Greek has the pair 'thick' : 'thicker' from the PIE etymon *bʰn̩ɡʰ- (established by cognate forms like Sanskrit bahú- 'abundant' since *bʰ is the only point of intersection between Greek p and Sanskrit b), in which the /p/ in the comparative is a result of levelling. Similarly, ~ 'come to know' from PIE *bʰewdʰ- has the future . Contrariwise, only /tʰ/ dissimilates before aspirated affixes like the aorist passive in /-tʰɛː/ and the imperative in /-tʰi/; /pʰ/ and /kʰ/ do not, as in 'speak!'.