bulb

5 definitions • 8 examples

a round root of some plants from which the plant grows:

tulip bulbs

I planted some spring bulbs which should be coming up soon.

a hollow, round part at the end of a glass tube in a thermometer (= a device used for measuring temperature) that holds liquid that will expand (= increase in volume) to show the temperature:

Most of the mercury (or other fluid) in a thermometer is in the bulb at the bottom.

The bulb of the sugar thermometer should not rest on the bottom of the pan.

a hollow, round, soft part at the end of a tube that can be pressed to force liquid or gas down through the tube, or to suck liquid or gas up through the tube :

I put the dropper in the vial and squeezed its rubber bulb, blowing a bubble of air into the liquid.

She suggests that parents of infants use saline drops and a suction bulb to help remove mucus.

a light bulb:

The bulb burned out in the kitchen.

a ball-like root from which some plants grow:

Lilies and tulips grow from bulbs.