Rastreador is the Portuguese name for the scouter, the eye-mounted scanner used by Saiyans and members of the Frieza Force in Dragon Ball Z. In the series the device beeps while it measures an opponent's battle power, often just before a villain realises they have underestimated their enemy. Clips of that scanning sound spread through anime edits, gaming videos and meme soundboards, where the Portuguese title stuck for many fans. It remains popular because the rising beeps instantly signal a power check, even for viewers who have never watched the show.