You can change the Room Name associated with each speaker in the Sonos app under the System Settings.

You can add a new Sonos device to a Room (that is a Sonos speaker label, not a room in your house) using the controller. You will be given a list of names you can use to label that Room or make your own name, it is also easy to change names using the Controller later. You can only use the Room label for a single Sonos, Stereo Pair or Home Theater group. For example I have Rooms office and office 1 to deal with wanting two non-stereo Paired in the office room in my house.

This is a bit confusing as Sonos marketing decided that there was something wrong with the previous, and far less confusing term Zone and it was banished form Sonos land.

So you put your Sonos in a room (house room, not Sonos Room) add it to your Sonos system and give it a Room name (has nothing to do with your house room, it could be kitchen but actually sitting in the bath) and then select it using the Room name, regardless of which room it is in.

Best to think of the Sonos settings as Zones, and your house as having rooms. Much easier to keep things straight in your mind that way.

Not related but if you already aren’t familiar:

And then if you happened to regularly want to play the same content on different Sonos rooms (e.g. kitchen + living room) you could create predefined groups for quick selection in System Settings > Manage > Groups. Or just group speakers on the fly.

Search for Preset groups in this guide:
https://www.sonos.com/en-us/guides/sonosapp