Ornithorhynchus
— Noun
– English
～ type genus of the family Ornithorhynchidae
Ornithorhynchus anatinus
— Noun
– English
～ small densely furred aquatic monotreme of Australia and Tasmania having a broad bill and tail and webbed feet; only species in the family Ornithorhynchidae
ornithosis
— Noun
– English
～ an atypical pneumonia caused by a rickettsia microorganism and transmitted to humans from infected birds
Orobanchaceae
— Noun
– English
～ brown or yellow leafless herbs; sometimes placed in the order Scrophulariales
orogeny
— Noun
– English
～ the process of mountain formation (especially by the upward displacement of the earth's crust)
orography
— Noun
– English
～ the science of mountains
oroide
— Noun
– English
～ alloy of copper and tin and zinc; used in imitation gold jewelry
orology
— Noun
– English
～ the science of mountains
orono
— Noun
– English
～ a university town in east central Maine on the Penobscot River to the north of Bangor
Orontium
— Noun
– English
～ one species of aquatic plant: golden club
Orontium aquaticum
— Noun
– English
～ aquatic plant of the southeastern United States having blue-green leaves and a spadix resembling a club covered with tiny yellow flowers
oropharyngeal
— Adjective
– English
～ of or relating to or located near the oropharynx
oropharynx
— Noun
– English
～ cavity formed by the pharynx at the back of the mouth
orotund
— Adjective
– English
～ ostentatiously lofty in style; "a man given to large talk"; "tumid political prose"
orotund
— Adjective
– English
～ (of sounds) full and rich; "orotund tones"; "the rotund and reverberating phrase"; "pear-shaped vowels"
orozco
— Noun
– English
～ Mexican painter noted for his monumental murals (1883-1949)
orphan
— Noun
– English
～ someone or something who lacks support or care or supervision
orphan
— Noun
– English
～ the first line of a paragraph that is set as the last line of a page or column