verb

refuse to declare valid.

he was offside and the goal was disallowed

reject,refuse,dismiss,say no to,ban,bar,block,stop,debar,forbid,prohibit,blackball,cancel,declare null and void,invalidate,overrule,quash,overturn,countermand,reverse,throw out,set aside,veto,embargo,proscribe,give the thumbs down to,squash