meeters?
a millimetre
The answer depends on what characteristic you wish to measure: its mass, length, volume etc.
It depends on what you mean by size: its length, volume, surface area or even its mass.
meters
You could use the centimeter (cm) or meter (m) unit to measure the length of a desk at school.
Meters should be used to measure the length of a tennis court in metric units.
I would use centimetres.
You would use a ruler and measure in millimeters or centimeters.
Millimeters or centimeters would be appropriate metric units to measure the length of a pin.
feet
Centimeters
mmeters
Centimetres
centimeter
Millimetre.
Milimeters