an inside joke in the U.S. military played on 'Boots' (newly arrived from boot camp).

squelch is a term used to fine-tune radios. it is a knob or button that controls whether or not background noise is heard on an open channel. it is used when communication is poor or lost and you are scanning your frequency/channel for any recognizable sounds.

telling someone to get a 'can' of squelch sends them to go ask someone, causing everyone who knows the joke to laugh. this is not always wise to send a boot to a Senior NCO for.
0311: hey Boot!

Boot: "Corporal?"

0311: "go down to supply and get a can of squelch. this radio's been acting up all morning and i can't get comm."

Boot goes to supply, waits in line, and then gets yelled at for wasting supply's time and their own. Usually ends with the Boot cleaning something unimaginable or guarding something insignificant for long, long, periods of time.
by Marines is capitalized January 21, 2011
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