Ornithogalum umbellatum
— Noun
– English
~ common Old World herb having grasslike leaves and clusters of star-shaped white flowers with green stripes; naturalized in the eastern United States
Osco-Umbrian
— Noun
– English
~ a group of dead languages of ancient Italy; they were displace by Latin
odd-toed ungulate
— Noun
– English
~ placental mammals having hooves with an odd number of toes on each foot
olive-drab uniform
— Noun
– English
~ military uniform of the United States Army; made from cloth of a dull olive color
Open University
— Noun
– English
~ a British university that is open to people without formal academic qualifications and where teaching is by correspondence or broadcasting or summer school
order Urticales
— Noun
– English
~ an order of dicotyledonous plants including Moraceae and Urticaceae and Ulmaceae
order Ustilaginales
— Noun
– English
~ parasitic fungi causing smuts; sometimes placed in class Tiliomycetes
oral poliovirus vaccine
— Noun
– English
~ an oral vaccine (containing live but weakened poliovirus) that is given to provide immunity to poliomyelitis
Oswald Veblen
— Noun
– English
~ United States mathematician (1880-1960)
ophthalmic vein
— Noun
– English
~ either of two veins that serve the eye; empties into the cavernous sinus
ovarian vein
— Noun
– English
~ one of the veins that drain the ovaries; the right opens into the inferior vena cava; the left opens into the left renal vein
oblique vein of the left atrium
— Noun
– English
~ a tributary of the coronary sinus; on the posterior wall of the left atrium
occipital vein
— Noun
– English
~ a vein that drains the occipital region