Infinities meaning : Endlessness, unlimitedness, absence of a beginning, end or limits to size. A number that has an infinite numerical value that cannot be counted. An idealised point which is said to be approached by sequences of values whose magnitudes increase without bound. A number which is very large compared to some characteristic number. For example, in optics, an object which is much further away than the focal length of a lens is said to be "at infinity", as the distance of the image from the lens varies very little as the distance increases further. The symbol ∞.