Synonyms for Two-way (same or very similar meaning)
WordNet sense 1 (supported by both sides):
two-party
WordNet sense 2 (free from party affiliation or bias):
nonpartisan, nonpartizan
WordNet sense 3 (having many parts or sides):
many-sided, multilateral
WordNet sense 4 (reactive or functioning or allowing movement in two usually opposite directions):
bidirectional
From the ODE community, based on WordNet
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