In dope growing, a "Hermie" is an hermaphrodite plant having both male and female reproductive capabilities. A plant that can fertilize itself and others. Not good for a pot garden trying to grow sinsemilla. The last thing you want in your garden is a viable male, unless you are trying to make more seed from the strain you are growing. A fertilized female will put all energy into seed production. An unfertilized female will use that energy to produce nice bud, loaded with THC. Sinsemilla = the Spanish words "Sin" (without) "Semilla" (seed) Males (and Hermies) cause seeds. NOT good.
It's been said that F+F pollination will produce more hermies, but IN MY BRIEF EXPERIENCE it doesn't. I assume the seeds I am growing now are from a crop that had some hermies in it because every seed that sprouted to date (30 or 40 seeds) has been a female, and no hermies to date. Since I used the last of my seeds form this source, I am hoping to get a hermie, or at least a male so I can keep this line going.