aleatory
capricious
episodic
freakish
indeterminable
occasional
sporadic
undeterminable
unforeseeable
accidental
adrift
adventitious
afloat
agnostic
alternating
ambiguous
amorphous
casual
causeless
chance
chancy
changeable
changeful
contingent
coquettish
destinal
desultory
deviable
dicey
dizzy
doubtful
doubting
dubious
eccentric
equivocal
erratic
extraordinary
faddish
fast and loose
fatal
fatidic
fickle
fitful
flickering
flighty
flirtatious
flitting
fluctuant
fluctuating
fluky
fortuitous
giddy
hesitant
hesitating
iffy
impetuous
bizarre
chaotic
confuse
contradictory
destructive
inexplicable
irrational
predictable
random
uncertain
unforeseen
unreliable
unstable
violent