What is the Certified Pool/Spa OperatorÂ® Certification Program? A CPOÂ® Certification provides individuals with the basic knowledge, techniques, and skills of pool and spa operations. This training has helped protect millions of swimmers by reducing hazards at aquatic facilities.
A year is the orbital period of the Earth moving in its orbit around the Sun. Due to the Earth's axial tilt, the course of a year sees the passing of the seasons, marked by changes in weather, the hours of daylight, and, consequently, vegetation and soil fertility.
Wiktionary(2.50 / 2 votes)Rate this definition: 1  decade(Noun) A series or group of ten things. a decade of soldiers. 2  decade(Noun) A period of ten years. 3  decade(Noun) A group of ten days under the French Revolutionary calendar.  decade(Noun) A series of ten Hail Marys in the rosary.