Synonyms for Helpful (same or very similar meaning)
WordNet sense 1 (being of use or service):
useful, utile
WordNet sense 2 (serving or acting as a means or aid):
instrumental
WordNet sense 3 (obliging; willing to do favors):
accommodating
WordNet sense 4 (done with or working with others for a common purpose or benefit):
cooperative
From the ODE community, based on WordNet
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