informal
■ pronoun nothing.
■ exclamation
1》 expressing denial or refusal.
2》 Brit. dated used as a warning that a person in authority is approaching. [perh. from the obs. phr. keep ~ 'to watch, guard'.]
■ verb chiefly N. Amer. put an end to; cancel: he ~ed the deal.
Origin
C18: from Ger., colloq. var. of nichts 'nothing'.