Sentence:  The big , 22 - year old shortstop , the 1960 American league `` rookie of the year '' , flew here late this afternoon from Baltimore , signed his <WSD>contract</WSD> for an estimated $ 15000 and was a spectator at tonight 's 5 - to 3 loss to Kansas City - the winless Birds ' sixth setback in a row . 
Meaning of the word marked with <WSD> tags:  a binding agreement between two or more persons that is enforceable by law