nonparticipant
noncooperator
nonmember
nonattendee
nonparticipating
nonparticipator
nonresponder
nonpartisan
neuter
noncompliant
balker
nonvoter
baulker
inactive
expatriate
expat
exile
uneligible
off board
absentee
noneligible
nonsharer
non partant
unparticipating
nonattender
nonsignatory
non-relative
nondelegate
nonqualifier
observer
opt out
forgoer
crasher
nonadherent
stayaway
AWOL
nonjoiner
nonsigner
nonrecipient
ineligible
lookers-on see most of the game
non-responder
per procurationem
forfeit
serononresponder
disqualification
nondriver
unsociable
nonparticipation
mute