[1] : WordNet (r) 2.0

unassertive
     adj 1: inclined to timidity or lack of self-confidence; "a shy
            unassertive person" ant: assertive
     2: not blatant or overly aggressive in manner or appearance; "a
        retiring disposition" syn: retiring
see also:
assertive retiring 

[2] : Moby Thesaurus II by Grady Ward, 1.0

34 moby thesaurus words for "unassertive":
   abject, accepting, acquiescent, agreeable, assenting, backward,
   bashful, complaisant, compliable, compliant, complying, consenting,
   diffident, modest, nondissenting, nonresistant, nonresisting,
   nonresistive, obedient, passive, rabbity, resigned, retiring,
   self-effacing, servile, shy, submissive, subservient, supine,
   timid, unassured, uncomplaining, unresistant, unresisting

Unassertive >> U Words
Unassertive, definition of term: Unassertive
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