a large solid piece of hard material, especially rock, stone, or wood, typically with flat surfaces on each side

a block of marble

a large single building subdivided into separate rooms, flats, or offices

a block of flats

a large quantity or allocation of things regarded as a unit

a block of shares

final examinations will be taken in a block at the end of the course

an obstacle to the normal progress or functioning of something

substantial demands for time off may constitute a block to career advancement

an emotional block

a flat area of something, especially a solid area of colour

cover the eyelid with a neutral block ofcolour

a pulley or system of pulleys mounted in a case

a simple pulley block