Farmer's Nail is to have one or more dirty finger nails and the dirt appears to be typical garden variety "dirt" or potting soil under the nails. However, Farmer's Nail is not regular dirt or soil but is actually feces which is accumulated under one or more finger nails as a direct result of either intentional fingering of a dirty shit plugged anus during a sexual act or from having one or more fingers slip through the toilet paper while wiping one's ass and getting ass dirt or fecal matter under the nails. Having Farmer's Nail does not mean that one did not wash their hands after an anal fingering or after slippage during a wipe job, just that one did not clean the feces from under their nails at the time of the wash job as they may not have known it was present. In most, but not all instances of Farmer's Nail, it is not left under the nail intentionally and is simply an oversight during the clean up process.

Farmer's Nail is also known as Mechanic's Nail which is more frequently used in the automotive industry.
Carl: Hi Gary. What have you been up to? From the looks of those fingers I would say you have been working in the garden this morning?
Gary: No I have not been in the yard working today. (Looking at nails) Oh No Bro. I had the worst Louisiana Tail Drop earlier this morning and made an absolute mess. I was wiping my sharted ass with both hands and my fingers kept slipping through the wet shat paper. Guess it got under the nails.
Carl: That is some nasty shit brahh! You got the worst case of Farmer's Nail I have ever seen. Go get a toothpick or a nail file and dig that shit out. Nasty.
by Eaton Holgoode April 11, 2014
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