Mere minor mechanical abrasions of the axilla and intercrural areas may be followed
by many forms of bacterial, yeast, or fungus infections. Often a complication of
participating in the world's favorite indoor sport. See illustration: Warning: very naughty.
http://academic.brooklyn.cuny.edu/classic/wilson/core/intercr.htm

intervolve
vt., vi.
3volved$, 3volv4ing 5< INTER3 + L volvere, to roll: see WALK6
1 to wind or roll up together; coil up
2 to involve or be involved with one another

As the old misquote goes, it takes two to tangle.

intrados
n.
5Fr < L intra, within + Fr dos < L dorsum, the back6 Archit. the inside curve or surface of an arch or vault: see ARCH1, illus.

And Oh, the promised introitus at apex of intrados!

intransigent
adj.
5Fr intransigeant < Sp intransigente < L in3, IN32 + transigens, prp. of transigere, to come to a settlement, TRANSACT6 refusing to compromise, come to an agreement, or be reconciled; uncompromising
n.
a person who is intransigent, esp. in politics
in[tran4si[gence or in[tran4si[gen[cy
n.

And beware the intransigent teasers who wont come across.

Mostly a legal term for evidence that may be presented in a court proceeding.
The card was subject to seizure and introducible in evidence since it was not discovered by means
of a search in the technical sense, but was plainly ...

Mostly a genetic technical term.
HOST-ASSOCIATED GENETIC DIFFERENTIATION IN THE GOLDENROD ... (PDF) - ... Consistent with this
historical estimate is the absence of detectable recombinant (hybrid and introgressant between host form) individuals in
contemporary ...

But it could be synonym for penetrating..........

in[tu[mes[cence 73mes4!ns8
n.
5Fr6
1 an intumescing or being intumesced
2 a swollen or enlarged organ or mass, as a tumor; swelling
in#tu[mes4cent
adj.

What Viagra promises to facilitate

intussuscept
vt.
5< L intus, within + susceptus, pp. of suscipere: see fol.6 to receive within, itself or into another part; specif., to telescope (one section of the intestines) into another; invaginate

A real four alarm surgical emergency . one segment of small bowel pushes inside another in a way
that obstructs circulation if not promptly treated can lead to necrosis, perforation, peritonitis, and death.