(a)uncertain, unsure, incertainlacking or indicating lack of confidence or assurance“uncertain of his convictions”, “unsure of himself and his future”, “moving with uncertain (or unsure) steps”, “an uncertain smile”, “touched the ornaments with uncertain fingers”
(a)uncertainnot established beyond doubt; still undecided or unknown“an uncertain future”, “a manuscript of uncertain origin”, “plans are still uncertain”, “changes of great if uncertain consequences”, “without further evidence his story must remain uncertain”
(s)changeable, uncertain, unsettledsubject to change“a changeable climate”, “the weather is uncertain”, “unsettled weather with rain and hail and sunshine coming one right after the other”