Causing your sexual arousal or physical attraction to dissipate (the sexual analogue to buzzkill or downer.) Literal meaning is "causing to become flaccid", but can also be used more generally to indicate loss of interest.
I was so turned on seeing that hot guy walk in, but his racist comments were totally flaccidating.
Yeah, she was sexy AF but her breath was majorly flaccidating.
Factinate is a garbage website that that steals people's posts from Reddit and re-posts them without their permission. So, to Factinate something, is essentially the act of stealing from one website and re-posting it somewhere else.