abcense absence
abridgement abridgment
accomodate accommodate
acknowledgment acknowledgement
airplane aeroplane
allright alright 
andy andrew
anemia anaemia
anemic anaemic
anesthesia anaesthesia
appologize appologise
archean archaean
archeology archaeology
archeozoic archaeozoic
armor armour
artic arctic
attachment attachement
attendence attendance
barbecue barbeque
behavior behaviour
biassed biased
biol biology
buletin bulletin
calender calendar
canceled cancelled
car automobile
catalog catalogue
cenozoic caenozoic
center centre
check cheque
color colour
comission commission
comittee committee
commitee committee
conceed concede
creating createing
curiculum curriculum
defense defence
develope develop
discription description
dulness dullness
encyclopedia encyclopaedia
enroll enrol
esthetic aesthetic
etiology aetiology
exhorbitant exorbitant
exhuberant exuberant
existance existence
favorite favourite
fetus foetus
ficticious fictitious
flavor flavour
flourescent fluorescent
foriegn foreign
fourty forty
gage guage
geneology genealogy
grammer grammar
gray grey
guerilla guerrilla
gynecology gynaecology
harbor harbour
heighth height
hemaglobin haemaglobin
hematin haematin
hematite haematite
hematology haematology
honor honour
innoculate inoculate
installment instalment
irrelevent irrelevant
irrevelant irrelevant
jeweler jeweller
judgement judgment
labeled labelled
labor labour
laborer labourer
laborers labourers
laboring labouring
licence license
liesure leisure
liquify liquefy
maintainance maintenance
maintenence maintenance
medieval mediaeval
meter metre
milage mileage
millipede millepede
miscelaneous miscellaneous
morgage mortgage
noticable noticeable
occurence occurrence
offense offence
ommision omission
ommission omission
optimize optimize
organise organize
pajamas pyjamas
paleography palaeography
paleolithic palaeolithic
paleontological palaeontological
paleontologist palaeontologist
paleontology palaeontology
paleozoic palaeozoic
pamplet pamphlet
paralell parallel
parl parliament
parlt parliament
pediatric paediatric
pediatrician paediatrician
pediatrics paediatrics
pedodontia paedodontia
pedodontics paedodontics
personel personnel
practise practice
program programme
psych psychology
questionaire questionnaire
rarify rarefy
reccomend recommend
recieve receive
resistence resistance
restaraunt restaurant
savior saviour
sep september
seperate separate
sept september
sieze seize
summarize summarise
summerize summarise
superceed supercede
superintendant superintendent
supersede supercede
suprise surprise
surprize surprise
synchronise synchronize
temperary temporary
theater theatre
threshhold threshold
transfered transferred
truely truly
truley truly
useable usable
valor valour
vigor vigour
vol volume
whack wack
withold withhold
yeild yield