off-the-cuff
on the hop
ad lib
spontaneously
extemporaneously
unrestrained
spur-of-the-moment
unscripted
semispontaneous
ad-libbed
unstudiedly
unpremeditated
on impulse
incident
unplanned
extemporary
on the fly
break into
unripely
extempore
preoccurrence
prolegomenously
previous
preparative
nonspontaneous
remain to be seen
ad hoc
unwittingly
unthoughted
spontaneousness
strained
semireflex
automatism
routine
anticipatively
unspontaneously
unsupposed
modus operandi
semistaged
fore-
all dressed up and nowhere to go
intuitive
precontemporaneous
fleetingly
find oneself
ultroneously
unprecocious
by accident
prepensely
precedently
off the top of one's head
ex tempore
premeditatedly
premeditatingly
upfront
occurrent
in advance
noninstantaneous
seasonable
expontaneous
transiently
inopportune
witting
unpremeditatedly
conscious
aforehand
unintendingly
purposed
forebegotten
precipitato
unintendedly
extemporarily
propaedeutic
contrived
unlooked for
advertent
uninstantiated
premeditatively
impromptu
fortuitously
crop up
noninitial
extemporally
foremade
ahead
unhabitual
leading
in due time
unanticipatedly
in a flash
nonsimultaneously
unreadily
nonintroductory
untimely