What is Grow A Beard?
1.
to show solidarity; to support a movement, protest or strike.
David Letterman and Conan O’Brien decided to grow a beard in solidarity of the writer's strike.
"You didn't support Paris during her jail stint, you failed to Grow a Beard."
See
2.
to perform oral sex upon a female (assuming one is male)
"man, im going home to grow a beard"
"last night I grew the biggest beard"
