"Compersion" is the secondhand feeling of happiness you get when you see someone else happy.
I feel compersion when I see a toddler happy; I don't know if I love her, but I do indeed feel compersion for her.
by Cheeku Naman April 4, 2019
A feeling of joy when a loved one invests in and takes pleasure from another romantic or sexual relationship.

Commentary: Compersion can be thought of as the opposite of "jealousy;" it is a positive emotional reaction to a loved one's other relationship. The term was coined by the Kerista Commune. It differs from candaulism in that compersion does not specifically refer to joy regarding the sexual activity of one's partner, but refers instead to joy at the relationship with another romantic and/or sexual partner. It is analogous to the feeling of joy a parent feels when their children marry or that best friends feel for each other when they are happy in a romantic relationship.
Example: "I feel compersion when I see my husband come home happy from spending time with his girlfriend. His happiness brings me happiness."
by W February 22, 2018
Compersion is the knowing that life and love is better when our partners feel more love in their lives. It's the joy and love YOUR feel when your partners are happy with their other partners, when you see different aspects of them, when their love makes your own relationships deeper.

NOT necessarily about arousal or cuckolding! o_O Compersion can involve arousal, it can be hot to hear about sexy times your partners have had with other people, but it ain't the main use for that word.
She felt a heart-melty compersive reaction to seeing her sweeties snuggle with other people cuz damn ain't that cute to see.
by manky titties August 5, 2018
A made up word, specifically used in the D/s community, based on the concept that submissives needs to deal with the fact that their Dom/me can fuck anyone they want and the submissive has to pretend to be happy with it. Does not normally work the other way around.
She stated that she was happy her Dom was ignoring her to pay attention to the new girl down the block, saying she felt compersion for her Dom's happiness but the broken dishes on the floor said differently.
by new york bella April 17, 2015
The act of living vicariously though one of your own girl/boyfriends because they chose to abandon you and spend quality-time with someone else. It is widely believed "compersion" is a self-preservation technique developed by individuals that self-identify as polyamorous.
Jack has developed a keen sense of compersion to maintain his sanity after his girlfriend Jill, went to shag her other boyfriend John.
by Karbowiak October 10, 2009