Sentence:  A similar analysis of Figure 6 for the 34 boys would necessitate quite a different conclusion about the predictive value of onset age in forecasting their attainment of the <WSD>pubescent</WSD> stage . 
Meaning of the word marked with <WSD> tags:  (of animals especially human beings) having arrived at the onset of puberty (the age at which sex glands become functional) but not yet fully mature