nutburger
crazyhead
wackadoodle
have bats in one's belfry
mad hatter
crackbrain
ding-a-ling
fruitcake
wingnut
nutbar
kook
crackpot
tapped
nutcase
nutter
wacko
whacko
mad as a cut snake
nutbag
have a screw loose
idiosyncratic
quizzical
odd bod
eccentrize
dotty
freako
off the deep end
space case
glaik
way out
strange person
spook
weirdy
weirdie
creep
weirdo
screw loose
oddball
balmy
crazo
full deckism
wackaloon
live one
spacy
doolally
eccentrical
cooked
superfreak
zonky
squirrelly
oddling
eccentrically
kooky
wack
loon
freak
fruitloop
odd fish
eccentricity
wifty
flip one's wig
odd man out
stunod
odd fellow
rocket
queer duck
queer bird
weirdar
crazyitis
nutzoid
asshead
crazy
arsehead
throw one's cap over the windmill
5150
oddment
loony tune
tonto
batshit
dingbat
nut job
loony
nutbaggery
cuckooness
clown shoe
headbanger
one's elevator doesn't go all the way to the top
idiosomic
oddballish
muppet
insane