Pacer

n. one who determines speed in a race; horse that sets the pace in a horse race; one who paces; pacemaker

For the US government documentation system, see PACER (law) The PACER project, carried out at Los Alamos National Laboratory in the mid-1970s, explored the possibility of a fusion power system that would involve exploding small hydrogen bombs (fusion bombs)—or, as stated in a later proposal, fission bombs—inside an underground cavity.
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Pacer can refer to:Pacer (train), a type of British trainEdsel Pacer, an American carAMC Pacer, an American carPiper PA-20 Pacer, an American light aircraftPacer is a brand of mechanical pencilPacer (album), an album by The AmpsPacer Stacktrain, an American intermodal freight transportation services companyPACER (law) (Public Access to Court Electronic Records), a court document retrieval systemPACER, a project which explored the idea of using H-bombs for power generation.PACER (Progressive Aerobic Cardiovascular Endurance Run), a test designed to test a peron's endurance and pacing by having them run back and forth a specified distance progressively fasterPacer, a standardbred horse moving in a specific way (see horse gaits and harness racing).Pacer, (Formerly Puffin Pacer) a type of small sail powered racing dinghy.
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Noun
1. a horse used to set the pace in racing
(synonym) pacemaker, pacesetter
(hypernym) racehorse, race horse, bangtail
(derivation) pace
2. a horse trained to a special gait in which both feet on one side leave the ground together
(hypernym) horse, Equus caballus
(derivation) pace

v. pasture, graze; run; browse; gnaw

(n.)
One who, or that which, paces; especially, a horse that paces.