etymon

The old French vairon signifies anything of two colours, and may possibly be the etymon of vaire.

I cannot admit any of these derivations, though perhaps my own etymon may not be deemed less irrelevant, viz.

Were, wert; worth, werth; word and werde, are derived from the same etymon and retain a similarity of meaning.

I am inclined to think, with the two first-mentioned lexicographers, that the etymon is πόσις, or potio.

Will you accept a French elucidation of the etymon of this word, which has sorely puzzled your correspondents?