I have a schematic and there's this symbol I don't understand. I tried reading list of circuit symbols but couldn't find a match.
It is used for the switch part of a connector, commonly for an audio connector where the connecter is used for an external speaker (or microphone) and the switch disables the internal speaker. The full symbol is like this:
(This picture calls the middle contact 'connect', IMO 'disconnect' would be more appropriate.)