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bicycle motocross

American  
[bahy-si-kuhl moh-toh-kraws, -kros, -sikuhl] / ˈbaɪ sɪ kəl ˈmoʊ toʊˌkrɔs, -ˌkrɒs, -ˌsɪkəl /

noun

Sports.
  1. BMX.


Etymology

Origin of bicycle motocross

First recorded in 1970–75