decease
perish
go
exit
pass away
expire
pass
kick the bucket
cash in one's chips
buy the farm
conk
give-up the ghost
drop dead
choke
croak
snuff it
change state (generic term)
turn (generic term)
die out (related term)
die off (related term)
die down (related term)
die down (related term)
be born (antonym)