1. Hindrance or obstruction that prevents a natural or desired outcome: Carson jokingly complained about the interference in his plans for vacation which was caused by his work schedule.
2. Involvement in something without any invitation or justification: Mason thoughtlessly used interferences at today's office meeting by interrupting the chairman, Mr. Thomas, at the beginning instead of waiting for the discussion part to take place.
3. In the game of football, the legal blocking of defensive players to protect and make way for the player carrying the ball: Jeannette's father played football and wore large shoulder pads to protect himself when he ran interference so his teammate could score a touch down.
4. The inhibition or prevention of clear reception of broadcast signals or the distorted portion of a received signal: The mountains and high winds caused much interference when Jasper tried to call his wife to explain why he would be late coming home.
5. The confusion or distortion that happens when old and new learning styles or information appear to contradict each other: The interference caused by the transition from teaching in a rote manner to a more inquiry based system sometimes frustrated the teachers. for example Mr. Black.
6. An assumption or a guess which is made based on little or no evidence: It seems that some lawyers try to present evidence during trials in such a way that the jury will choose the interferences that favors their clients.

Electromagnetic radiation, caused by natural electrical disturbances in the atmosphere; atmospherics; sferics; strays: Atmospheric interferences interfere with radio systems.

The radio frequency electromagnetic radiation originated principally in the irregular surges of charge in thunderstorm lightning discharges.

Atmospherics are heard as a quasi-steady background of crackling noise (static) on certain radio frequencies, such as those used to broadcast AM radio signals.

Since any acceleration of electric charge leads to emission of electromagnetic radiation, and since the several processes involved in propagation of lightning lead to very large charge accelerations, the lightning channel acts like a huge transmitter, sending out radiation with frequencies of the order of 10 kHz.

Any interference in radio communications caused by terrestrial magnetism or the Earth's magnetic field: Geomagnetic noises are unwanted radio frequencies that are caused by fluctuations in the geomagnetic field of the Earth.