In a manner that helps; with the quality of assisting or aiding (rare or archaic construction).
From the present participle 'helping' (help + -ing) combined with the adverb suffix '-ly.' This is an older or less standard formation compared to 'helpfully.'
This word is so rare that most modern spell-checkers don't recognize it, yet it was used occasionally in 17th-century English as writers experimented with different ways to modify verbs.
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