(Latin: within, inside, on the inside)

Borrowed from late Latin intra-; closely related to inter-, "between". The use of intra- is largely a product of modern times, occurring in words of common and technical vocabulary, where once it was generally a term used in science and the academic world.

While some words are borrowings from Medieval and even Late Latin, few if any come from Classical Latin.

—Based on information from Barnhart Dictionary of Etymology
1. In the eye.
2. Within or introduced into the inside of the eyeball.

Intraocular pressure is the pressure within the eye.

intraocular lens, IOL
An artificial lens made of plastic, silicone, acrylic, or other material that is implanted inside the eye during cataract surgery.

Removal of the cataract and insertion of the intraocular lens typically takes about an hour and does not require hospitalization.

The intraocular lens is implanted within the capsule, which provides permanent support for the lens. It is never handled or adjusted, as a contact lens might be.

1. Situated or occurring within an enclosure; shut off from public sight; private; secluded; retired.
2. Situated in the parietal region of the brain.
3. Within the wall of an organ.
intrapsychic (adjective)
The psychological dynamics that occur inside a person's mind without any reference to the individual's exchanges with other people or events.
intrapulmonic (adjective)
A reference to that which is in or occurring within the lungs.
Within the scrotum.
1. Within the spinal canal or within a sheath.
2. Within a sheath, for example, cerebrospinal fluid that is contained within the dura mater. It also refers to drugs administered into the cerebrospinal fluid bathing the spinal cord and brain.
3. Within either the subarachnoid or the subdural space.

An intrathecal injection (often simply called "intrathecal") refers to an injection into the spinal canal (intrathecal space surrounding the spinal cord), as in a spinal anaesthesia or in chemotherapy. This route is also used for some infections, particularly post-neurosurgical infections.

Inside a vessel.
intravenous (adjective)
1. Within or administered by means of a vein; such as, an injection.
2. Existing within or entering through a vein or veins.

Intravenous comes from intra-, "within" or "via", and venous, "of the veins". Often in hospitals patients will be given water or nutrients from intravenous drips from plastic bags of liquid connected to a tube going into a person's arm.

It's a way to get needed nutrition and fluid into a person's body without waiting for the digestive system to process it.

intravenously (adverb)
A reference to a dose of medicine or nutrients administered from a drip, down through a hollow needle inserted into a patient's vein; and so, in an intravenous manner: "The patient was fed intravenously because it was the fastest way to deliver fluids and medications throughout his body."

Within a word.

Cross references of word families related directly, or indirectly, to: "internal organs, entrails, inside": ent-; enter-; fistul-; incret-; inter-; splanchn-; viscer-.