Helpful; providing aid or assistance; inclined to help (archaic or rare).
From 'help' plus the suffix '-some,' which creates adjectives meaning 'full of' or 'characterized by' (as in 'handsome,' 'fearsome'). This is an older formation largely superseded by 'helpful.'
The suffix '-some' was much more productive in Middle English for creating adjectives, but 'helpful' eventually won out—probably because '-ful' felt more natural than '-some' for this particular meaning.
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