I. “+ adjective
Etymology: Middle English, from un- (I) + certain
1.
a. : not fixed in time : being of indefinite date
the exact moment of departure is uncertain
b. : indeterminate in number, amount, or extent
engagements being irregular, the income is uncertain — Official Register of Harvard University
a tract of uncertain acreage — American Guide Series: Maryland
2. : not certain to occur : problematical
her success in new parts was very uncertain — G.B.Shaw
3.
a. : not known, demonstrated, or apparent beyond doubt : open to doubt : questionable
unless further evidence is found, his story must remain uncertain
b. : ambiguous
told him, in no uncertain terms, what he thought of his behavior
c. : not clearly identified, defined, or located
a fire of uncertain origin destroyed the capitol — American Guide Series: Pennsylvania
a play of uncertain authorship
the two bartenders, sallow women of uncertain age — William Sansom
4.
a. : not fixed in place, direction, or course : wandering
the silver thread of water tracing its uncertain course along the valley floor — E.A.McCourt
b. : not assured, consistent, or dependable in action, behavior, or effect : erratic , unreliable
ramshackle buildings lean over the water on their uncertain stilts — American Guide Series: New York City
a gun with a rather uncertain trigger — D.M.MacKay
c. : not settled or fixed in character, quality, or state : subject to accident, chance, or change : unpredictable
everything is uncertain about the army — Walt Whitman
leading a somewhat uncertain existence — Fortnight
uncertain health
5.
a. : not having certain knowledge or conviction : not assured : doubtful
tolerant but never uncertain of his convictions — W.A.White
b. : not definitely directed : undecided
of great ambition, but uncertain aim
c. : hesitant , tentative
touching the flowers, the ornaments, the books with uncertain fingers — Edith Sitwell
an uncertain gentleness in his tone — Marguerite Steen
6. : changeable , fickle , variable
an uncertain breeze
an uncertain friend
a beautiful and uncertain time, cold and wet and dry and warm — Josephine Johnson
• un·cer·tain·ly adverb
• un·cer·tain·ness noun
II. adverb
: uncertainly