Noun : The sun is the center of the solar system. ,the center of a problem. ,His family is the center of his life. ,a shipping center. ,a youth center; The company has a complete recreation center in the basement. ,a flood-relief center; a crisis center. ,chocolate candies with fruit centers. ,a garden center; a nutrition center. ,Unfortunately, his homeland has always lacked a responsible Center. ,the vasomotor center.    From Dictionary.com. 

Verb (used with object) : She centered the clock on the mantelpiece. ,He centered his novel on the Civil War. ,A small brass star centered the tabletop. ,to center the lens of a telescope; to center the work on a lathe.    From Dictionary.com. 

Verb (used without object) : The interest of the book centers specifically on the character of the eccentric hero. Political power in the town centers in the position of mayor. ,Shops and municipal buildings center around the city square.    From Dictionary.com.