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hydroaerobics

American  
[-ai-roh-, hahy-droh-uh-roh-biks] / -ɛəˈroʊ-, ˌhaɪ droʊ əˈroʊ bɪks /

noun

(used with a plural verb)
  1. aerobic exercises performed in water, as in a swimming pool.


Etymology

Origin of hydroaerobics

hydro- 1 + aerobics