What is the X in X-mas?
interference in·ter·fer·ence (ĭn'tər-fēr'əns)
The variation of wave amplitude that occurs when waves of the same or nearly the same frequency come together.
The condition in which infection of a cell by one virus prevents superinfection by another virus.
The condition in which superinfection by a second virus prevents effects that would result from infection by either virus alone, even though both viruses persist.
The disturbance that results when two waves come together at a single point in space; the disturbance is the sum of the contribution of each wave. For example, if two crests of identical waves arrive together, the net disturbance will be twice as large as each incoming wave; if the crest of one wave arrives with the trough of another, there will be no disturbance at all.
Note: One common example of interference is the appearance of dark bands when a light is viewed through a window screen.
To provide justification, protection, etc: The average personnel department merely pushes paper, occasionally running interference for the line managers who actually make hiring decisions
[1947+; the primary football use is found by 1929]