The adapter (1) has an attachment (4), which is fitted onto a container mouth closed by a closure element (18) in an attachment direction in a sealing manner, where a penetration element is mounted on the attachment in such a way that the penetration element is movable between a rest position (R) and a withdrawal position using guide units. A connector stub (3) is arranged transversely, particularly substantially perpendicularly, with respect to the attachment direction (H), particularly on the penetration element. Independent claims are included for the following: (1) a dispenser for a fluid and (2) a transfer device for the transfer of fluid from a container into a dispenser using an arrangement.
