oligoprecursor
An oligodendrocyte precursor or progenitor cell

oligoprecursors
plural of oligoprecursor

oligoteratoasthenospermia
Oligoteratoasthenozoospermia.

oligoxyloglucan
An oligomeric form of xyloglucan

oligoxyloglucans
plural of oligoxyloglucan

oliodendroglioma
Misspelling of oligodendroglioma.

olo
A highly saturated impossible color shade of blue-green produced by directly stimulating the "m" ("green") cone cells, approximating the below

omegasome
A cup-shaped protrusion from the endoplasmic reticulum that serves as a platform for autophagosome biogenesis in mammalian cells.

omegasomes
plural of omegasome

omenta
plural of omentum

omentum
Either of two folds of the peritoneum that support the viscera.

omentums
plural of omentum

omnipause
A type of neuron that has a role in the stability of the saccadic system

omnipauses
plural of omnipause

omo
Clipping of omorashi.

omodysplasia
A severe shortening of the limbs and dysmorphism of the skull

omoideum
The pterygoid bone.

omorashi
A paraphilia or sexual practice involving arousal from the feeling of one or someone else having a full urinary bladder, sometimes including erotic denial of bathroom access.

omphalolith
A periumbilical mass that may form due to the accumulation of sebum and keratin.

onahole
An artificial vagina for use in masturbation.

onaholes
plural of onahole

onchosphere
Alternative form of oncosphere.

onchospheres
plural of onchosphere

oncocyte
A large, granular cell, having many mitochondria, found in salivary and certain endocrine glands.

oncocytes
plural of oncocyte

oncogene
Any gene that contributes to the conversion of a normal cell into a cancerous cell when mutated or expressed at high levels.

oncogenes
plural of oncogene

oncosis
ischemic cell death: a process characterized by mitochondrial swelling, cytoplasm vacuolization, and swelling of the nucleus and cytoplasm

oncosphere
An embryonic form of a tapeworm, enclosed in a spherical membrane armed with six hooks

oncospheres
plural of oncosphere

onychodysplasia
dysplasia of the nails

onychodystrophies
plural of onychodystrophy

onychodystrophy
Dystrophic changes in nails, such as deformations, malformations or discolourations.

onychostroma
The matrix or sensitive tissue of the finger, forming the bed of the nail.

ooblast
A cell that develops into an ovum; a germinal epithelium giving rise to ova.

ooblasts
plural of ooblast

oocyesis
Ovarian pregnancy: the type of ectopic pregnancy that occurs within an ovary.

oocyst
A reproductive cell in certain fungi.
A thick-walled spore in the lifecycle of some parasitic protozoans that develops into sporozoite.

oocysts
plural of oocyst

oocyte
A cell that develops into an egg or ovum; a female gametocyte.

oocytes
plural of oocyte

oogamete
The female gamete; the egg cell or oosphere.

oogametes
plural of oogamete

oolemma
The cell membrane of an oocyte.

oonuclei
plural of oonucleus

oonucleus
The nucleus of an oosphere.

oophorectomies
plural of oophorectomy

oophorectomy
Surgical removal of one or both ovaries.

oophoron
Synonym of ovary.

oophoropexy
Surgical fixation of a displaced ovary by suturing to the abdominal wall.

oophorosalpingectomies
plural of oophorosalpingectomy

oophorosalpingectomy
Removal of one or both ovaries and the corresponding fallopian tubes.

oophorotomy
An incision into an ovary.

ooplasm
The cytoplasm of an egg or ovum

ooplasms
plural of ooplasm

oosik
The baculum (penile bone) of a walrus, often sold as a souvenir to tourists in Alaska.

oosiks
plural of oosik

oosperm
The ovum, after fusion with the spermatozoon in impregnation.

ootid
The haploid cell, produced by meiotic division of a secondary oocyte, that is a nearly mature ovum.

ootids
plural of ootid

ootype
The part of the oviduct of certain trematodes in which the ova are completed by being furnished with yolk, and, by secretion from the Mehlis glands, with a shell.

ootypes
plural of ootype

ophthalmodynamometry
The measurement of blood pressure in the blood vessels of the retina.

opisthia
plural of opisthion

opisthion
The middle of the posterior margin of the foramen magnum of the skull.

opisthomastigote
A stage in unicellular life-cycle, typically trypanosomes, where the flagellum is posterior of the nucleus, and passes through a groove in the cell body.

opisthomastigotes
plural of opisthomastigote

opisthosoma
The posterior segment of the two-part body structure of chelicerates. Often used interchangeably with abdomen.

opisthosomas
plural of opisthosoma

opisthosomata
plural of opisthosoma

opistothorax
A wormlike segmented extension to the thorax.

opponens
Short for opponens digiti minimi (“a muscle of the hand”).
Short for opponens pollicis (“a muscle of the hand”).

oprelvekin
recombinant interleukin 11, a thrombopoietic growth factor that directly stimulates the proliferation of hematopoietic stem cells and megakaryocyte progenitor cells and induces megakaryocyte maturation resulting in increased platelet production

opsismodysplasia
A skeletal dysplasia involving delayed bone maturation

optocoele
The cavity of one of the optic lobes of the brain in many animals.

optocoeles
plural of optocoele

optogenetics
A science that combines optics and genetics, aiming at controlling cellular processes with light. The cells are made responsive to light using genetics and then activated using specific wavelengths.

optogram
An image of external objects fixed on the retina by the photochemical action of light on rhodopsi.

optograms
plural of optogram

optography
The production of an optogram on the retina by the photochemical action of light on the visual purple; the fixation of an image in the eye.

orbiculares
plural of orbicularis

orbicularis
A muscle surrounding an opening.

orbitales
plural of orbitalis

orbitalis
A muscle that controls protrusion of the eyeball.

orbitohyoideus
A large, tapering muscle, in some frogs, associated with the ceratohyal

orchi
Clipping of orchiectomy.

orchialgia
Pain in the testes.

orchidalgia
Synonym of orchialgia.

orchidectomies
plural of orchidectomy

orchidectomy
Synonym of orchiectomy.

orchidopexies
plural of orchidopexy

orchidopexy
Alternative form of orchiopexy.

orchie
Clipping of orchiectomy.

orchiectomies
plural of orchiectomy

orchiectomy
The surgical removal of one or both testes.

orchies
plural of orchie

orchiopexies
plural of orchiopexy

orchiopexy
A procedure for fixation of a testis, often to move an undescended testicle into the scrotum and keep it there.

oreboat
A vessel used to transport iron ore on the Great Lakes

organella
Synonym of organelle.

organellae
plural of organella

organelle
A specialized structure found inside cells that carries out a specific life process (e.g. ribosomes, vacuoles).

organelles
plural of organelle

organellomics
The branch of cell biology that studies the structure and function of organelles in an organism.

organification
The stabilization of a material within an organ.

organifications
plural of organification

organlessness
Absence of organs.

organoapatite
Any organic derivative of apatite, used in artifical bone applications.

organoculture
The tissue culture of whole organs

organocultures
plural of organoculture

organogeneses
plural of organogenesis

organogenesis
the formation and development of the organs of an organism from embryonic cells

organogenies
plural of organogeny

organogeny
Organogenesis.

organography
The scientific description of the structure and function of the organs of living organisms.

organomegalies
plural of organomegaly

organomegaly
The abnormal enlargement of an organ

organonymy
The designation or nomenclature of organs.

organopathies
plural of organopathy

organopathy
The homeopathic theory that certain remedies act locally in specific organs.

organophyly
The direct study of the evolution of the forms of biological organs and systems of organs rather than observation of its supposed ontogenic recapitulation.