Origins
The word 'wealth' is a Middle English coinage that originally meant something much broader and more humane than its modern sense suggests. It was formed from 'wele' (well-being, happiness, prosperity) with the abstract noun suffix '-th,' on the analogy of 'health' (from 'hale,' whole). Just as 'health' is the state of being whole and sound, 'wealth' was the state of being well — prosperous, fortunate, and happy. The narrowing to mean specifically 'abundance of money and possessions' occurred gradually during the fourteenth and fifteenth centuries, a semantic contraction that reveals shifting cultural values.
The root 'wele' descends from Old English 'wela' (prosperity, riches, well-being), from Proto-Germanic *walō, from PIE *wel- (to wish, to will, to choose). This PIE root is extraordinarily productive in English. It produced 'well' (in good manner), 'will' (desire, volition), 'willing,' 'voluntary' (from Latin 'voluntārius,' from 'voluntās,' will), 'benevolent' (from Latin 'bene volēns,' well-wishing), and 'malevolent' (from 'male volēns,' ill-wishing). The conceptual cluster is consistent: wishing, willing, choosing, and the state of having what one wishes for.
The parallel construction of 'health' and 'wealth' is linguistically elegant. 'Health' comes from Old English 'hǣlþ' (wholeness, being sound), from 'hāl' (whole, sound — the source of 'whole,' 'hale,' 'holy,' and 'heal'). 'Wealth' comes from 'welthe' (well-being), from 'wele' (well, prosperous). Both use the '-th' suffix that appears in 'growth,' 'depth,' 'breadth,' 'strength,' 'youth,' and 'truth' — all abstract nouns formed from adjectives or shorter nouns. The pair 'health and wealth' has been a formulaic expression in English since the Middle Ages, preserved in toasts and greetings.
Development
The original breadth of 'wealth' is preserved in the word 'commonwealth' — literally 'the common well-being,' a term for a political community organized around shared prosperity. When England declared itself a 'Commonwealth' under Oliver Cromwell in 1649, the word explicitly invoked the original sense of 'wealth' as general welfare, not mere monetary richness. The modern 'Commonwealth of Nations' retains this older meaning.
The word 'welfare' is another compound preserving the original sense: 'well' + 'fare' (to go, to travel) — literally 'going well,' prospering. The modern association of 'welfare' with state assistance programs is a twentieth-century development.
The semantic narrowing of 'wealth' from 'well-being' to 'money' is itself a commentary on cultural history. In a society where material possessions increasingly determined social standing, the word for general prosperity contracted to mean the most visible form of prosperity. The older, broader sense — where wealth included health, happiness, reputation, and spiritual grace — gradually receded. The etymology remembers what the modern usage has forgotten: that being wealthy was once understood as being well, in the fullest sense.