- Unlimited extent of time, space, or quantity; eternity;
boundlessness; immensity. - Unlimited capacity, energy, excellence, or knowledge; as,
the infinity of God and his perfections. - Endless or indefinite number; great multitude; as an
infinity of beauties. - A quantity greater than any assignable quantity of the
same kind. - That part of a line, or of a plane, or of space, which is
infinitely distant. In modern geometry, parallel lines or planes are
sometimes treated as lines or planes meeting at infinity.