Definition of "Ping" :
noun: a sharp high-pitched resonant sound (as of a sonar echo or a bullet striking metal)
noun: a river in western Thailand; a major tributary of the Chao Phraya
verb: send a message from one computer to another to check whether it is reachable and active
"Ping your machine in the office."
verb: contact, usually in order to remind of something
"I'll ping my accountant--April 15 is nearing."
verb: hit with a pinging noise
"The bugs pinged the lamp shade."
verb: make a short high-pitched sound
"The bullet pinged when they struck the car."
verb: sound like a car engine that is firing too early
"The car pinged when I put in low-octane gasoline."