In the US, we call them "Traffic Circles".
The adjective round can have the synonyms circular, ball-shaped, annular, coiled, or curled. The noun round (cycle) has synonyms including stage, sequence, series, or turn. The noun round (bullet) has the synonyms cartridge, ammunition, load, or shell.
get round, avoid, circumvent, depart from, deviate from, pass round, detour round
The adjective round has the synonyms coiled, curled, spherical, and circular.
gather, assemble, accumulate, round up, collect
round tripper, going yard, dinger, four bagger
period, term, fit, spell, turn, interval, round, series, session, cycle, sequence, stint
Synonyms encircle, circle, circumnavigate, compass, girdle, girth, loop, ring, round
A wheel is a round device to roll a vehicle on. The wheel rotates around the axle which is fixed to the vehicle.
The term "bicycle" refers to a single two-wheeled vehicle that is typically ridden by one person. If you want to refer to multiple bicycles, you would use the plural form "bicycles."
A tall vehicle maybe a double-decker going round a tight turn at a high speed
put sheets of metal round the outside of the car.
They are synonyms.