A container of a plastic material has a container body (1) for receiving a fluid and a neck part (7) adjoining the container body (1). The neck part (7) has at its free end a discharge opening for the fluid closed by a head part (11) and covered by a cap (19). The cap (19) interacts with individual blocking elements via a retaining ring (21), starting from an attachment position of the cap (19). Rotary motions in both directions of rotation are permitted along a predetermined path of travel. During a further screw-on motion beyond the predetermined path of travel, a part of second blocking elements completely passes over assigned first blocking elements, and in so doing the head part (11) is penetrated by the opening part of the cap (19). During a subsequent unscrewing motion of the cap (19) for the purpose of releasing the discharge opening, the retaining ring (21) is disengaged from the cap (19) and, in the process, is secured on the neck part (7) at least temporarily against rotation in the unscrewing direction by at least one blocking element.