Like the engine, the straight 6 is six men in a line involved in anal intercourse. Unlike the rods and cylinders going up and down in an engine the straight 6 men move their hips back and forth in unison until climax.
Disclaimer: there is NOTHING “straight” about this except the line of men.
Hey guys this football game is boring, let’s do shots and line up and stuff our butts in a straight 6
Referring to the appearance of a woman who has absolutely nothing to offer in the chest. A woman who is Straight up and down like six o clock looks exactly like what the term implies---there are no boobs to break up the straight line appearance when you look at her from top to bottom. Most prominent when viewed from the side.
"Man did you see that chick?"
"Yeah....she is OK but she has no tits..."
"Yeah I know what you mean....she's straight up and down like 6 o clock!"