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.
Something that is seen as foreplay is occurring on the opposite partner's body or revealed about their character that is so repulsive it instantly causes the penis to become flaccid. Although at the time of discovery is so fascinating that it is nearly impossible to look away or focus elsewhere.
Brenda took her bra off and underneath were nipples shaped like furry stop signs, it was flaccinating.
We were just about to have sex when Donna asked if we could bring a donkey into the picture, now that flaccinated me.
I was blind sighted and flaccinated when Kaili took her panties off and a 2 foot afro bush popped into the air.