The Collaborative International Dictionary of English v.0.48:
Internal \In*tern"al\, a. [L. internus; akin to interior. See
1. Inward; interior; being within any limit or surface;
inclosed; -- opposed to external; as, the internal parts
of a body, or of the earth.
2. Derived from, or dependent on, the thing itself; inherent;
as, the internal evidence of the divine origin of the
3. Pertaining to its own affairs or interests; especially,
(said of a country) domestic, as opposed to foreign; as,
internal trade; internal troubles or war.
4. Pertaining to the inner being or the heart; spiritual.
With our Savior, internal purity is everything.
5. Intrinsic; inherent; real. [R.]
The internal rectitude of our actions in the sight
of God. --Rogers.
6. (Anat.) Lying toward the mesial plane; mesial.
Internal angle (Geom.), an interior angle. See under
Internal gear (Mach.), a gear in which the teeth project
inward from the rim instead of outward.
Syn: Inner; interior; inward; inland; inside.
[1913 Webster] Internal-combustion