Diffident

Diffident
adj.
Definition: 1. hesitant due to lack of self-confidence; 2. reserved or restrained in behavior
Synonyms: reserved, unassertive, bashful, restrained, hesitant, distrustful, doubtful, insecure, modest, self-effacing, sheepish
Antonyms: outgoing, loquacious, brazen, unabashed

Sample Sentences:

Kate didn't know anyone at the party, so she was diffident whenever someone approached her to chat.

Her intelligence was masked by her diffident behavior, which often made people think that she was dumb or didn't have anything to say.

Usage:

  http://www.time.com/time/magazine/article/0,9171,843759,00.html

http://www.bbc.co.uk/news/science-environment-19383607

Paragraph:

 Diffident comes from the latin word fidere, "to trust," with the addition of the "dis-" prefix, which makes its meaning negative. A diffident person is distrustful of something, usually of making a mistake in a social situation, or seems distrustful. The noun diffidence refers to hesitation or reluctance. For a memory trick, think, diffident is different/opposite of confident. The latin prefix con means "with," so confident means "with trust," while diffident means "without trust."

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