Acoustic the amount of resonance in a room.
Acquired material anything included in the production that you have not recorded or shot yourself.
Action cue used by the director to cast or presenter to start once the camera is rolling.
Actuality sound in radio the sound naturally occurring in a location.
Ambient sound the sound or ambience of a room – this could just be the silence.
Aperture the setting on a camera which controls the size of the iris and changes the amount of light coming into the camera.
Backlight a light behind the object in a camera frame. Gives depth to the image.
Big close up(BCU) very close shot of a person or object.
Blocking the process of setting the action in a scene, usually drama.
Camera left/right position ...