A now relic term from the 40's indicating an expression of genuine amazement that makes a male want to get his knob out and bosh one out.
Tarquin - "Look at the chebs on her!"

All - "knob out!"
by Kears July 7, 2008
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An expression of genuine amazement that makes a male want to get his knob out and masturbate
"look at the jugs on that - Knob out"
by Secret Bunny July 11, 2008
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Employing one's knob outside the confines of marital bliss.
Amelia: Things have not been the same between Charles & I over the last few weeks. He seems so... distant.
Isabella: What do you mean? Last time I saw you both, you seemed so happy together.
Amelia (staring into her tea): He isn't as... "attentive" as he used to be. I'm afraid he might be knobbing out.
by Carstairs November 11, 2013
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