Noun
1. an interval during which a recurring sequence of events occurs;
"the neverending cycle of the seasons"2. a series of poems or songs on the same theme;
"schubert's song cycles"3. a periodically repeated sequence of events;
"a cycle of reprisal and retaliation"4. the unit of frequency; one Hertz has a periodic interval of one second
5. a single complete execution of a periodically repeated phenomenon;
"a year constitutes a cycle of the seasons"6. a wheeled vehicle that has two wheels and is moved by foot pedals