exceptional
unusualness
unique
for once
exceptionably
freak accident
remarkable
stretch a point
uncommon
exceptionableness
unusual
sporadicalness
antrin
geason
extraordinary
atypical
offbeat
sporadic
out of the way
lippening
freakish
rareness
exceptive
outlier
exceptionability
rare as hen's teeth
ultrarare
rarefactional
uncommonness
abnormalcy
different
abnormalism
rare bird
rare as a four-leaf clover
rara avis
attenuate
excipient
anomalism
throwable
unexampled
strange
unorthodox
peculiar
rare
rarity
unusuality
catch
shenanigans
rareish
exceptor
estival
seldomness
aestival
semirare
way-out
raresome
out of the common
peak
rare as rocking horse shit
singularity
distinguishing characteristic
phenomenon
peculiarity
distinctive feature
one of those things
rash
exceptionlessness
rarer than hens' teeth
not grow on trees
blizzard
seld
nonrare
narrowly
unmiraculous
carveout
superrare
mutant
exceptant
isanomal
unwonted
on accident
accidental
scarce
duh factor
uncommonly
unexpectable
dead donkey
one-shot
special pleading
for this once
rarefiable
special pleader
one in a million
by accident