dif·fi·dent (dĭfĭ-dənt, -dĕnt′)
Lacking or marked by a lack of self-confidence; shy and timid: He was too diffident to express his opinion.
[Middle English, from Latin diffīdēns, diffīdent-, present participle of diffīdere, to mistrust : dis-, dis- + fīdere, to trust; see bheidh- in the Appendix of Indo-European roots.]
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