Menu Toggle
Merriam-Webster Logo
Games & Quizzes
Games & Quizzes
Word of the Day
Grammar
Wordplay
Word Finder
Thesaurus
Join MWU
Shop
Books
Merch
Settings
My Words
Recents
Account
Log Out
More
Thesaurus
Join MWU
Shop
Books
Merch
Log In
Username
My Words
Recents
Account
Log Out
Est. 1828
Words That Start With O
Browse the Dictionary
a
b
c
d
e
f
g
h
i
j
k
l
m
n
o
p
q
r
s
t
u
v
w
x
y
z
0-9
bio
geo
« Previous
Next »
-o
...
oblast
oblasti
...
obtention
obtest
...
octagon
octagonal
...
odontorhynchous
Odontormae
...
officiator
officinal
...
oildom
oil drill
...
Old Norse
Old North French
...
Olpidium
olycook
...
once or twice
once-over
...
on-glide
ongoing
...
on the go
on the ground
...
oosorption
oosorptive
...
operability
operable
...
opobalsamum
opopanax
...
orally
oral method
...
ordinant
ordinariate
...
oriently
orientness
...
ortho-
orthoarsenate
...
Osmeridae
Osmerus
...
-ota
OTA
...
outbrawling
outbrawls
...
outjumping
outjumps
...
outpunched
outpunches
...
outtrade
outtraded
...
overbreed
overbreeding
...
overeat
overeaten
...
overindustrialise
overindustrialised
...
overprescribing
overprescription
...
overstrength
overstress
...
ovulation
ovulatory
...
oxyhydrogen
oxyhydrogen blowpipe
...
ozotype
« Previous
Next »
Word of the Day
lollygag
See Definitions and Examples
»
Get Word of the Day daily email!