uncertain

1. a сомнительный, неясный, точно не известный

the date of their arrival is uncertain — дата их прибытия точно не известна

2. a неопределённый

a lady of uncertain age — дама неопределённого возраста

3. a изменчивый, ненадёжный, капризный

uncertain weather — изменчивая погода

4. a неуверенный, колеблющийся, нерешительный, сомневающийся

I am uncertain of success — я не уверен в успехе

uncertain landing — неуверенное приземление

Синонимический ряд:

1. doubtful (adj.) ambivalent; borderline; clouded; doubtable; doubtful; dubitable; fishy; impugnable; indistinct; precarious; queasy; shady; shaky; suspect; suspicious; uneasy; unsure

2. moot (adj.) arguable; contested; debatable; disputable; disputed; dubious; moot; mootable; problematic; problematical; questionable

3. obscure (adj.) amphibological; double-edged; double-faced; dusky; equivocal; murky; nubilous; obscure; opaque; sibylline; tenebrous; unclear; unexplicit; unintelligible; vague

4. open (adj.) ambiguous; cloudy; indefinite; indeterminate; nebulous; open; sceptical; undecided; undetermined; unfixed; unresolved; unsettled

5. vacillating (adj.) double-minded; faltering; halting; hesitant; hesitating; indecisive; irresolute; pendulous; shilly-shally; shilly-shallying; tentative; timid; undecisive; vacillant; vacillating; vacillatory; wavering; weak-kneed; whiffling; wiggle-waggle; wobbly

6. variable (adj.) alterable; capricious; chance; chancy; changeable; erratic; fickle; fluctuant; fluid; freakish; iffy; incalculable; inconsistent; inconstant; insecure; irregular; lubricious; mercurial; mutable; shifty; slippery; temperamental; ticklish; undependable; unpredictable; unreliable; unsafe; unsettled; unstable; unsteady; variable; volatile; whimsical

Антонимический ряд:

definite; fixed; positive; regular; sure