opposite-sex pairs
opposite regulation
opposite response
opposite result
opposite sense
opposite sex
opposite side
opposite sign
opposite strand

opposite trend
opposite way
opposition
opposition parties
oppositional defiant disorder
oppression
opsin gene
opsonic activity
optic atrophy
optic cup

optic disc
optic disc appearance
optic disc parameters
optic ganglia
optic lobes
optic nerve
optic nerve atrophy
optic nerve damage
optic nerve disease
optic nerve function

optic nerve head
optic nerve hypoplasia
optic nerve injury
optic nerve involvement
optic neuritis
optic neuropathy
optic pathway
optic radiations
optic tectum
optic tract

optic vesicle
optical
optical aberrations
optical Kerr effect