(1):

(n.) The act or state of interfering; as, the stoppage of a machine by the interference of some of its parts; a meddlesome interference in the business of others.

(2):

(n.) The mutual influence, under certain conditions, of two streams of light, or series of pulsations of sound, or, generally, two waves or vibrations of any kind, producing certain characteristic phenomena, as colored fringes, dark bands, or darkness, in the case of light, silence or increased intensity in sounds; neutralization or superposition of waves generally.

(3):

(n.) The act or state of interfering, or of claiming a right to the same invention.