Synonyms thesaurus that start with the letter: O (3,640 entries)

ochre
ochroma
ochroma lagopus
ochronosis
ochs
ocimum
ocimum basilicum
ockham
ockham's razor
oconee bells
ocotillo
oct
octad
octadecanoic acid
octagon
octagonal
octahedron
octal
octal digit
octal notation
octal number system
octal numeration system
octameter
octane
octane number
octane rating
octanedioic acid
octangular
octans
octant
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