PWR is a "Pressurized Water Reactor" using (light) water under pressure as the primary coolant. The Chernobyl block #4 RBMK-1000 was certainly a PWR.

While the precise mechanism by which the #4 reactor in Chernobyl was destroyed in 1986 was rooted in the flawed design combined with unsafe operation, this does not mean that other reactor designs cannot fail catastrophically with loss of containment and release of radioactive material. Particularly when operated outside of their specification through operator error, accidents or a combination thereof.