inessential
unessential
accessory
accident
accidental
addendum
addition
additional
adjunct
adrift
adscititious
adventitious
aleatory
appendage
appurtenance
appurtenant
ascititious
auxiliary
back-burner
beside the mark
beside the point
beside the question
casual
circumstantial
collateral
conditional
contingency
contingent
de trop
dinky
dispensable
excess
expendable
expletive
extra
extraneous
extrinsic
fortuitous
gratuitous
happenstance
immaterial
impertinent
in excess
inadmissible
inapplicable
inapposite
inappreciable
inappropriate
incidental
inconsequent
inconsequential
alpha-shift
ancillary
carboxylic
custodial
directionless
earth-moving
easy-care
excitatory
excitotoxic
fine-material
host-nation
ill-adapted
jewel-encrusted
mission-essential
newsworthy
non-significant
noncombatant
omega-3
religion
salt-laden
screechy
short-chain
sulfonic
telluric
unaffordable
uncork
ungraspable
unionize
unlikeable
confidential
consequential
credential
deferential
differential
essential
existential
exponential
influential
jurisprudential
nonresidential
potential
preferential
presidential
providential
prudential
quintessential
residential
reverential
sequential
tangential
torrential
vice-presidential
mandatory
necessary
required