Stepped keycap
Provided by the ASK Keyboard Dictionary
Aka/also known as: hatted keycap (for double-stepped only)
A keycap is stepped if it has a noticeably lowered space on one or both sides of its top face. Steps can be present on keycaps larger than a single unit and used to either make a keycap feel more distinct if you're trying to find it quickly/without looking or to reduce the need for a stabiliser by forcing the user to press the keycap a certain way. Since the Enhanced Keyboard's introduction, it's been typical for IBM and family keyboards to at least have single-stepped Caps Lock and (if applicable) stepped ISO enter keys to help define them. However, keyboards like the IBM Personal Computer's used two steps for all non-spacebar keycaps larger than 1 unit so the user must press them at their centre.
