precarious (adj.)

• ambiguous
• borderline
• chancy
• critical
• dangerous
• delicate
• desultory
• dicey
• difficult
• doubtful
• dubious
• equivocal
• hairy
• hazardous
• iffy
• indecisive
• infirm
• insecure
• insubstantial
• open
• perilous
• problematic
• provisional
• questionable
• risky
• sensitive
• shaky
• shifting
• shifty
• slippery
• slippy
• temporary
• tentative
• ticklish
• touch-and-go
• touchy
• treacherous
• tricky
• uncertain
• undependable
• unpredictable
• unreliable
• unsettled
• unsound
• unstable
• unsteady
• unsubstantial
• unsure
• untrustworthy