rotary
n. B2 Upper Intermediate US //ˈɹoʊtɝi// UK //ɹˈəʊtəɹi// ro·tary
n. moving or working in a circle around a central point. You use this to describe machines or parts that spin.
n. characterised by or involving motion in a circle around an axis. Often describes mechanical components or systems designed to rotate continuously.
The rotary blade spins very fast to cut the grass.
Old telephones used a rotary dial that you had to turn with your finger to call a number.
The engineer explained that the rotary engine provides a higher power-to-weight ratio than traditional piston engines because of its unique circular motion.
Usage
Typically placed before the noun it modifies; often used in technical or mechanical contexts.