Motards yell all the time, wear clothes with USMC logos all over them, have a ridiculous amount of usmc tattoos, and use the word oorah! excessively. They also like to call cadence while they walk around when not marching a platoon. A motard is usually some private or private first class who hasn't even been deployed.
Marine 2: "Oh my god, that motard over there won't shut the fuck up!"
Motard: "OORAH MARINES! I FUCKING LOVE PT AT 0500 IN THE MORNING! BY THE WAY I GOT ANOTHER moto TATTOO LAST NIGHT! OORAH!"
A person who is generally gauche or lacking social polish, or in more extreme cases, any social skill at all.
Cpl Schmuckatelli: "Yeah I know, he is so motivated he actually thinks it's wrong to drink underage just because the Marine Corps said so. What a fucking Motard!"