idle wheel

Từ điển WordNet v3.1 - WordNet Dictionary

noun

a pulley on a shaft that presses against a guide belt to guide or tighten it
• Syn:
idle pulley, idler pulley
• Hypernyms:
pulley, pulley-block, pulley block, block

• Từ đồng nghĩa / Synonyms:
  idle pulley, idler pulley