with nothing marked, written, printed, or recorded on it

blank paper

a blank tape

not filled in; with spaces to be filled in

a blank form

dazed or nonplussed

He stared in blank dismay

expressionless

a blank stare

temporarily without thought, memory, or understanding

My mind went blank

lacking interest, variety, or change

a blank prospect

having a plain or undecorated surface, or an unbroken surface where an opening is usual

a blank wall

an empty space, e.g. one to be filled in on a form

a form, etc with blanks to be filled in

a void, without thought, memory, or understanding

My mind was a blank

a vacant or uneventful period

a piece of material prepared to be made into something, e.g. a key or coin, by a further operation

= blank cartridge