Following are all the spur-of-the-moment like words, in the list below.
IMPROMPTU
100% like spur-of-the-moment
UNPREPARED
99.79% like spur-of-the-moment
SPONTANEOUS
33.37% like spur-of-the-moment
AD HOC
33.37% like spur-of-the-moment
OFFHANDED
33.37% like spur-of-the-moment
OFFHAND
33.37% like spur-of-the-moment
EXTEMPORARY
33.37% like spur-of-the-moment
AUTOSCHEDIASTIC
33.37% like spur-of-the-moment
REFLEXIVE
33.37% like spur-of-the-moment
IMPROVISATIONAL
33.37% like spur-of-the-moment
SPORADICAL
33.37% like spur-of-the-moment
AD LIB
33.37% like spur-of-the-moment
BY THE BY
33.37% like spur-of-the-moment
ON-THE-SPOT
33.37% like spur-of-the-moment
CASUAL
33.37% like spur-of-the-moment
IMPROVISATORIAL
33.37% like spur-of-the-moment
SERENDIPITOUS
33.37% like spur-of-the-moment
FORTUITOUS
33.37% like spur-of-the-moment
ADVENTITIOUS
33.37% like spur-of-the-moment
CHANCE
33.37% like spur-of-the-moment
PROTEMPORANEOUS
33.37% like spur-of-the-moment
PRECIPITATE
33.37% like spur-of-the-moment
PLUMP
33.37% like spur-of-the-moment
SUPERADVENIENT
33.37% like spur-of-the-moment
OFF-HANDED
33.37% like spur-of-the-moment
RANDOMISH
33.37% like spur-of-the-moment
SEMIOCCASIONAL
33.37% like spur-of-the-moment
COINCIDENTAL
33.37% like spur-of-the-moment
RUSHED
33.37% like spur-of-the-moment
EPISODIC
33.37% like spur-of-the-moment
PROMPT
33.37% like spur-of-the-moment
HAPHAZARDOUS
33.37% like spur-of-the-moment
PRECIPITATED
33.37% like spur-of-the-moment
HURRIED
33.37% like spur-of-the-moment
ADVENTIVE
33.37% like spur-of-the-moment
COINSTANTANEOUS
33.37% like spur-of-the-moment
PERIPATETIC
33.37% like spur-of-the-moment
MINUTE-TO-MINUTE
33.37% like spur-of-the-moment
PRETIMELY
33.37% like spur-of-the-moment
PLAYFUL
33.37% like spur-of-the-moment
SPADISH
33.37% like spur-of-the-moment
FREELY
33.37% like spur-of-the-moment
SHIFTFUL
33.37% like spur-of-the-moment
MINUTELY
33.37% like spur-of-the-moment
FAST-HANDED
33.37% like spur-of-the-moment
LIGHTNING-QUICK
33.37% like spur-of-the-moment
SPIKEWISE
33.37% like spur-of-the-moment
HEADLONG
33.37% like spur-of-the-moment
SIMULTANEOUS
33.37% like spur-of-the-moment
FREEHANDED
33.37% like spur-of-the-moment
SPRINKLY
33.37% like spur-of-the-moment
FREEWILL
33.37% like spur-of-the-moment
SIDE
33.37% like spur-of-the-moment
SCRATCH
33.37% like spur-of-the-moment
INTERJECTURAL
33.37% like spur-of-the-moment
BRISK
33.37% like spur-of-the-moment
EARLY
33.37% like spur-of-the-moment
ACCELERATED
33.37% like spur-of-the-moment
MAKESHIFTY
33.37% like spur-of-the-moment
PLAIN-SPOKEN
33.37% like spur-of-the-moment
ADVERTENT
33.37% like spur-of-the-moment
INCIDENTAL
33.37% like spur-of-the-moment
PROJECTILE
33.37% like spur-of-the-moment
DISPATCHFUL
33.37% like spur-of-the-moment
STOCHASTIC
33.37% like spur-of-the-moment
FIRST-TIME
33.37% like spur-of-the-moment
SUMMARY
33.37% like spur-of-the-moment
OUT AND ABOUT
33.37% like spur-of-the-moment
RAPID FIRE
33.37% like spur-of-the-moment
SUBSULTORY
33.37% like spur-of-the-moment
QUICKSMART
33.37% like spur-of-the-moment
INGENERATE
33.37% like spur-of-the-moment
LOOSE-HANDED
33.37% like spur-of-the-moment
PERCURSORY
33.37% like spur-of-the-moment
SCATTERED
33.37% like spur-of-the-moment
NOW-A-DAYS
33.37% like spur-of-the-moment
SCRAWLED
33.37% like spur-of-the-moment
RANDOMLIKE
33.37% like spur-of-the-moment
IN THE WIND
33.37% like spur-of-the-moment
RAPID-FIRE
33.37% like spur-of-the-moment
SUPERVENIENT
33.37% like spur-of-the-moment
INCITANT
33.37% like spur-of-the-moment
SHORT-WINDED
33.37% like spur-of-the-moment
SEMIFRANTIC
33.37% like spur-of-the-moment
FORWARD
33.37% like spur-of-the-moment
FORTHRIGHT
33.37% like spur-of-the-moment
SALTATORY
33.37% like spur-of-the-moment
BURSTWISE
33.37% like spur-of-the-moment
SCATTERSHOT
33.37% like spur-of-the-moment
WILLY-NILLY
33.37% like spur-of-the-moment
RANDOMWISE
33.37% like spur-of-the-moment
QUICK
33.37% like spur-of-the-moment
PLAINSPOKEN
33.37% like spur-of-the-moment
INSINUATORY
33.37% like spur-of-the-moment
QUICKISH
33.37% like spur-of-the-moment
AMBAGIOUS
33.37% like spur-of-the-moment
CIRCUMFORANEOUS
33.37% like spur-of-the-moment
CONCURRENT
33.37% like spur-of-the-moment
INTERJECTORY
33.37% like spur-of-the-moment
ULTRACASUAL
33.37% like spur-of-the-moment