Pump dispenser and containers

A pump attachable to a fluid container having a neck to which the pump is attached, the pump comprising:

• a pump body defining a pump chamber, the pump body having a locating formation engaging the container neck, and a plunger reciprocable relative to the pump body in a pumping stroke to alter the volume of the pump chamber;
• a lock mechanism comprising respective lock formations of the plunger and pump body, the lock mechanism having a locked condition wherein the plunger is locked against reciprocation and an unlocked condition wherein the plunger can reciprocate for pumping, and wherein a release movement of the lock mechanism from the locked condition comprises a relative rotation of the plunger and pump body around an axis of the plunger;
• and
• a catch mechanism comprising respective catch formations of the plunger and pump body which are engageable selectively in a locked condition of the lock mechanism, to prevent or inhibit the release movement thereof, and
• wherein a body/neck rotation stop mechanism provided by an interlock engagement between the pump body and the container neck to inhibit relative rotation thereof.