Synonyms for Assistant (same or very similar meaning)
WordNet sense 1 (a person who contributes to the fulfillment of a need or furtherance of an effort or purpose):
help, helper, supporter
WordNet sense 2 (of or relating to a person who is subordinate to another):
adjunct
WordNet sense 3 (lower in rank or importance):
low-level, subordinate
From the ODE community, based on WordNet
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