This is a phrase used when saying that married women sleep around with other males that she is not married to. Just because a woman is married (and has a ring), doesn't mean she doesn't want her hole plugged by someone else.
Friend: Hey, that girl is really cute, but she's married so I can't mess with her.
You: Hey, a ring doesn't plug a hole. Go for it.
by skghskg June 2, 2010
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