Synonyms for Secondary (same or very similar meaning)
WordNet sense 1 (coil such that current is induced in it by passing a current through the primary coil):
secondary coil, secondary winding
WordNet sense 2 (inferior in rank or status):
inferior, lowly, petty, subaltern, junior-grade, lower-ranking
WordNet sense 3 ((sometimes followed by `to') minor or casual or subordinate in significance or nature or occurring as a chance concomitant or consequence):
incident
WordNet sense 4 (experienced at secondhand):
vicarious
WordNet sense 5 (not as a direct effect or consequence):
indirect
WordNet sense 6 (accompany, concomitant):
collateral
WordNet sense 7 (functioning in a subsidiary or supporting capacity):
auxiliary, subsidiary
WordNet sense 8 (allowing a choice):
alternate, alternate
WordNet sense 9 (of lesser importance or stature or rank):
minor
WordNet sense 10 (lower in rank or importance):
low-level, subordinate
From the ODE community, based on WordNet
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