
Outing (the noun) vs. Outing (the verb)
The noun refers to the former. The verb refers to the latter.
When we "out" ourselves in the world of kink, we are telling the larger community--beyond the BDSM community--that we are into the lifestyle.

Other times, a collar can be more "vanilla" in that the collar can look like a necklace, a bracelet, a ring, an anklet, or some other kind of jewelry that denotes commitment. The one who wears the collar belongs to the person who gifted the collar and collared the person.
Some make their commitment public by having a collaring ceremony with close friends and family as witness. This kind of ceremony is as important and meaningful as a wedding. While ceremonies vary in nature, the meaning is the same: the persons committing to one another are doing so to solidify their union. Amen.