Finding it: The stop is simply the centre of Adamas village near the ferry pier — there is no separate terminal building or numbered address.
Worth knowing before you rely on this: Milos Buses is a private operator, not a KTEL — its own site (milosbuses.com and its Greek contact page) publishes no phone number or address for the Adamas terminal, only an email and a coach-rental mobile number. The phone above comes from a single third-party airport-transport page that mislabels the operator 'KTEL Milou'; treat it as unverified.