Sentence:  One <WSD>growth</WSD> center in a short bone - distal phalanx of the second finger - was chosen as an example for discussion here , primarily because epiphyseal diaphyseal fusion , the maturity indicator for Completion in long and short bones , occurs in this center for girls near the menarche and for boys near their comparable pubescent stage . 
Meaning of the word marked with <WSD> tags:  (biology) the process of an individual organism growing organically; a purely biological unfolding of events involved in an organism changing gradually from a simple to a more complex level