When you take a poop that is so big that there is a 100% chance of it clogging the toilet. One performs a manual dump by taking the log out of the toilet (preferably with rubber gloves), putting it into a plastic bag and then taking a walk of shame to the outside garbage.

This is generally due to constipation. Very common in kratom users.
*taking a shit*

*glances in bowl*

Me: “I’ll get the gloves, this is a manual flush. If you stepped on this turd you would probably break your ankle.”
by danasp_42 May 11, 2020
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1. A method by which one might intervene when a toilet is about to overflow, often due to an atypically large dump clogging the fixture. It involves pouring water into the bowl to balance out the displacement which a typical or automated flush without clogging would normally do. One must act fast in such a situation, resorting to the use of a nearby trash can or other receptacle in which to collect water from the tub or sink and then quickly dump into the impending explosion of the clogged toilet bowl.

2. A rare hand in poker where the player folds, citing and displaying greater interest in masturbating than in continuing to play.
1. "Holy eff, how big was your fucking turd, man? That's gonna flood this place! Quick, do a manual flush!"

2. "Jeremy's always dope to hang with, but when it comes to poker, he's more into the manual flush and coming, if you know what I mean..."
by PicklePuss November 15, 2013
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