From The Collaborative International Dictionary of English v.0.48 [gcide]:
1. physical exercises performed in a sustained and strenuous fashion designed to cause a temporary increase in respiration rate and heart rate, such a running, swimming, walking, or calisthenics. Calisthenic sessions in groups, performed by following a leader in moving to a rhythmic musical accompaniment, are a popular form of aerobics. [PJC.]
From WordNet (r) 3.0 (2006) [wn]:
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Eye and Pyramid BANKING REFORM CHALLENGE