Nouns

(n)center, centre, middle, heart, eyean area that is approximately central within some larger region“it is in the center of town”, “they ran forward into the heart of the struggle”, “they were in the eye of the storm”
(n)center, centre, midpointa point equidistant from the ends of a line or the extremities of a figure
(n)center, centrea place where some particular activity is concentrated“they received messages from several centers”
(n)center, centrethe sweet central portion of a piece of candy that is enclosed in chocolate or some other covering
(n)kernel, substance, core, center, centre, essence, gist, heart, heart and soul, inwardness, marrow, meat, nub, pith, sum, nitty-grittythe choicest or most essential or most vital part of some idea or experience“the gist of the prosecutor's argument”, “the heart and soul of the Republican Party”, “the nub of the story”
(n)center, centre, center of attention, centre of attentionthe object upon which interest and attention focuses“his stories made him the center of the party”
(n)center, centre, nerve center, nerve centrea cluster of nerve cells governing a specific bodily process“in most people the speech center is in the left hemisphere”
(n)center, centrea building dedicated to a particular activity“they were raising money to build a new center for research”

Verbs

(v)center, centremove into the center“That vase in the picture is not centered”
(v)concentrate, focus, center, centre, pore, rivetdirect one's attention on something“Please focus on your studies and not on your hobbies”