The Suppletion reference article from the English Wikipedia on 24-Jul-2004
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Suppletion

Time you got around to sponsoring a child
In linguistics and etymology, suppletion is the use as an inflected form of a word of an entirely different word that is not cognate to the uninflected form. Here are some examples:

Language Adjective Etymology Comparative/superlative Etymology
English good OE gOd, akin to OHG guod, Sanskrit gadhya "what one clings to" better/best OE betera, akin to bOt "remedy", Sanskrit bhadra "fortunate"
bad perhaps from OE bæddel "hermaphrodite" worse/worst OE wyrsa, akin to OHG wirsiro
French;
Spanish;
Italian
bon; bueno; buono Latin bonus, from OL duenos, akin to Sanskrit duva "reverence" meilleur; mejor; migliore Latin melior, akin to multus "many", Gk mala "very"
mauvais; malo; male† Latin malus pire; peor; peggiore Latin pejor, akin to Sanskrit padyate "he falls"

† This is an adverbial form ("badly"); the Italian adjective is itself suppletive (cattivo, akin to "captive").