a) A momentary partial or complete loss of picture and/or sound caused by such things as dust, dirt on the videotape or heads, crumpled videotape, or flaws in the oxide layer of magnetic tape.

Uncompensated dropout produces white or black streaks in the picture.

b) Drop in the playback radio frequency level, resulting from an absence of oxide on a portion of the videotape, causing no audio or video information to be stored there. Dropout usually appears as a quick streak in the video.