Sentence:  The word `` binomial '' means `` of two names '' or `` of two terms '' , and both usages apply in our work : the first to the names of the two outcomes of a binomial trial , and the second to the terms p and * * f that represent the <WSD>probabilities</WSD> of `` success '' and `` failure '' . 
Meaning of the word marked with <WSD> tags:  a measure of how likely it is that some event will occur; a number expressing the ratio of favorable cases to the whole number of cases possible