tracker

Definition

Agent noun of track; one who, or that which, tracks or pursues, as a man or dog that follows game.

Etymology

From track + -er.

Example Sentences

• "On Friday night, eight US Air Force KC-135 Stratotankers took off from Altus, Oklahoma, according to data from FlightRadar24. Over Kansas the tankers refueled two groups of planes, identified on air traffic control audio by their callsigns MYTEE11 FLT and MYTEE21 FLT. The callsign MYTEE has previously been associated with special activity flights by B-2 bombers, and multiple flight trackers on social media said the planes being refueled were B-2 bombers out of Whiteman Air Force Base in Missouri."
• "While she and Mr. Fetterman were often in different places, she would turn up at events early so she could shoot and post photos of the crowds, the lines, the people. At most events there was a tracker: a guy from the Oz team who monitored the goings-on."
• "Trackers have broken out of the demoscene, are are^([sic]) now in use by thousands of professional musicians. It's not uncommon to hear about people using trackers on DJ forums, and electronic music production communities[…]"