DIFFIDENT
diffident, shy, timid, unsure
(adjective) lacking self-confidence; “stood in the doorway diffident and abashed”; “problems that call for bold not timid responses”; “a very unsure young man”
diffident
(adjective) showing modest reserve; “she was diffident when offering a comment on the professor’s lecture”
Source: WordNet® 3.1
Etymology
Adjective
diffident (comparative more diffident, superlative most diffident)
(archaic) Lacking confidence in others; distrustful.
Lacking self-confidence; timid; modest
Synonyms: timid, modest
Source: Wiktionary
Dif"fi*dent, a. Etym: [L. diffidens, -entis, p. pr. of diffidere;
dif- = dis + fidere to trust; akin to fides faith. See Faith, and cf.
Defy.]
1. Wanting confidence in others; distrustful. [Archaic]
You were always extremely diffident of their success. Melmoth.
2. Wanting confidence in one's self; distrustful of one's own powers;
not self-reliant; timid; modest; bashful; characterized by modest
reserve.
The diffident maidens, Folding their hands in prayer. Longfellow.
Syn.
– Distrustful; suspicious; hesitating; doubtful; modest; bashful;
lowly; reserved.
Source: Webster’s Unabridged Dictionary 1913 Edition