W: (adj) central (serving as an essential component) "a cardinal rule"; "the central cause of the problem"; "an example that was fundamental to the argument"; "computers are fundamental to modern industrial structure"
W: (v) center (center upon) "Her entire attention centered on her children"; "Our day revolved around our work"
W: (n) centering [Related to: center] (the concentration of attention or energy on something) "the focus of activity shifted to molecular biology"; "he had no direction in his life"