Rename "New Identity"
TorBrowser can't to change or clear your identity. Torbutton can to clear history, to close tabs, to send newnym signal to Tor's controller by one click.
Tor by newnym signal can't to change or clear your identity. Tor can discard old circuits and begin to build new one. Circuit can't to be used as identity. IP address of exit node can't to be used as identity too (here you can discuss about ownership, leases, assigns, and nats at final).