orbifold
A topological space in which every small enough neighborhood is homeomorphic to a quotient of real space by the action of a finite group.

orbifolds
plural of orbifold

orbities
plural of orbity

orbity
A bereavement by loss of parents or children; the state of being orbate; orbation.

orc
Any of several large, ferocious sea creatures, now especially the killer whale.

orcharding
The growing of fruit in an orchard.
The hobby of visiting orchards.

orchet
orchard

orchets
plural of orchet

orchidaria
plural of orchidarium

orchidarium
An orchid garden.

orchidariums
plural of orchidarium

orcs
plural of orc

ordoliberalism
A political philosophy that emphasizes the desirability of the government establishing rules to maximize the potential of the free market to produce results.

oread
A mountain nymph; an anthropomorphic appearance of the spirit of a mountain.

oreads
plural of oread

oredelf
The right to mine under a piece of land.

ork
Obsolete spelling of orc (“killer whale”).

orks
plural of ork

oronym
The toponym of a mountain.

oronyms
plural of oronym

orphanotrophies
plural of orphanotrophy

orphanotrophy
A hospital for orphans.
The act of supporting orphans.

orthochoanite
Any nautiloid cephalopod of the suborder Orthochoanites

orthohedra
plural of orthohedron

orthohedron
A figure, somewhat like a cube but with two square faces and four rectangular faces

orthohedrons
plural of orthohedron

orthohelium
form of the helium atom in which the spins of the two electrons form a triplet state (a state with definite total spin).

oshona
Synonym of floodplain.

osieries
plural of osiery

osiery
A willow plantation.

osite
guano from the island of Sombrero, Anguilla

osteoporosities
plural of osteoporosity

osteoporosity
An area of osteoporosis

osteria
A small local restaurant in (usually rural) Italy.

osterias
plural of osteria

osterie
plural of osteria

ostikanate
The region governed by an ostikan.

ostikanates
plural of ostikanate

ostleries
plural of ostlery

ostlery
hostelry (inn)

ostmark
The currency unit of the former German Democratic Republic (aka GDR, DDR, East Germany) until 1990, abbreviated DDM.

ostmarks
plural of ostmark

ostrog
A small Russian fort, typically wooden, encircled by a palisade wall.

ostrogs
plural of ostrog

ottariid
Any sea lion of the family Otariidae

ottariids
plural of ottariid

oubliette
A dungeon only accessible by a trapdoor at the top.

oubliettes
plural of oubliette

outclinic
An outpatient clinic

outclinics
plural of outclinic

outdraft
An outward current, often specifically a river current pulling toward a downstream dam.

outdrafts
plural of outdraft

outground
Ground situated at a distance from the house; outlying land.
Alternative spelling of out ground.

outgrounds
plural of outground

outharbor
Alternative spelling of outharbour.

outharbors
plural of outharbor

outharbour
In Newfoundland and Labrador, any city, town, or village having a harbour, other than the main port of St. John's.

outharbours
plural of outharbour

outhut
An outbuilding in the form of a hut.

outhuts
plural of outhut

outlodging
A lodging outside the college bounds at Oxford or Cambridge.

outlodgings
plural of outlodging

outlot
A plot of undeveloped land, sometimes without access to public roads, designated by a developer on a plat for future construction or noted for its unsuitability to be designated a full lot.
A lot that corresponds with an in-town lot, being an open space on the edge of town where the owner can grow some crops and, in some cases, pasture some livestock.

outlots
plural of outlot

outparcel
A plot of land in a commercial shopping center development reserved for the later construction of smaller buildings, often restaurants.

outparcels
plural of outparcel

outparish
A parish lying outside the walls of, or in a remote part of, a town.

outparishes
plural of outparish

outpicket
A military picket or outpost.

outpickets
plural of outpicket

outport
A port city or harbor which is secondary to a main port; it may be a distant one or a nearby auxiliary one.
Any city, town, or village having a port, other than the main port of St. John's.

outports
plural of outport

outremer
An area beyond the sea.

outremers
plural of outremer

outstater
Someone from a different state.
Someone from outstate (the part of a state outside the major metropolitan areas).

outstaters
plural of outstater

outstreet
A street remote from the centre of a town.

outstreets
plural of outstreet

outvillage
An outlying village.

outvillages
plural of outvillage

outwash
The sediment (mostly sand and gravel) deposited by water flowing from a melting glacier.

outwashes
plural of outwash

overcroft
A room between the vaulting and the roof of a church

overcrofts
plural of overcroft

overdevelopment
Excessive development; the state or quality of being overdeveloped

overexcess
A particularly excessive quantity, amount or number; a vast excess of something; the state of being overexcessive.

overexcesses
plural of overexcess

overkingdom
A unit composed of several kingdoms and presided over by an overking; an empire.

overkingdoms
plural of overkingdom

overlearnedness
Excessive learning; the quality or state of being overlearned.

overlordship
The position or quality of being an overlord.
The realm of overlords.

overmantle
The region above a mantlepiece.

overmantles
plural of overmantle

overoccupation
Excessive occupation; the state of being occupied by too many; overcrowding.

ovonics
A form of electronics that uses materials able to change from an electrically non-conducting state to a semiconducting state shown by glass of special composition upon application of a certain minimum voltage.

oxengate
Synonym of oxgang.

oxengates
plural of oxengate

oxgang
The area of land that could be plowed by an ox in a year, ¹⁄₈ hide or carucate and notionally 15 acres.
The similar Scottish concept, ¹⁄₈ of a ploughgate and notionally 12+¹⁄₂ or 13 Scottish acres.

oxgangs
plural of oxgang

oxgate
Synonym of oxgang.

oxgates
plural of oxgate

oxyhornblende
A variety of hornblende in which most of the iron has been oxidized to the ferric state, Fe3+.

oxytrauma
trauma due to excess oxygen, typically received from a hospital ventilator

oxytraumas
plural of oxytrauma

oysterbank
A bank or bed of oysters.

ozoner
A drive-in movie theater.

ozoners
plural of ozoner

paceway
A racetrack for horses.

paceways
plural of paceway

paddleboarding
A water sport in which participants are propelled by a swimming motion using their arms while lying or kneeling on a paddleboard or surfboard in the ocean

paedicatio
Alternative spelling of pedicatio.

pagar
A fence, in parts of Asia.

pagars
plural of pagar

pagast
A small rural district in Latvia.

pagasts
plural of pagast

paideia
An Athenian system of education designed to give students a broad cultural background focusing on integration into the public life of the city-state with subject matter including gymnastics, grammar, rhetoric, music, mathematics, geography, natural history, and philosophy
The epitome of physical and intellectual achievement to which an Ancient Greek citizen could aspire; societal and cultural perfection.
An early model of Christian higher learning having theology as its chief subject.
A pedagogical system focusing on providing children with a broad and balanced education.

paindoo
A villager; rustic; hick.

paindoos
plural of paindoo

paiza
A tablet of authority in the Mongol Empire.

paizas
plural of paiza

pakhanate
Another term for mafia state.

pakhanates
plural of pakhanate

pakihi
An area of open land (chiefly in western parts of the South Island), especially when waterlogged.

pakihis
plural of pakihi

palaceful
As much as a palace can hold.

palacefuls
plural of palaceful

paladar
A small family-run restaurant in a Cuban home

paladares
plural of paladar

paladars
plural of paladar

palaeobasin
Alternative form of paleobasin.

palaeobasins
plural of palaeobasin