noun

A key on a typewriter or computer keyboard that causes the carriage or cursor to move backward.

I’ve been digging through pictures cursing myself for not documenting my work better, typing the details from my notes then suddenly, I broke the backspace key on my computer.

intransitive verb

Move a typewriter carriage or computer cursor back one or more spaces.

The < BS > markers show where I hit the BackSpace key – note that the text I was backspacing over remains in the log.