nail in the coffin of

(redirected from a nail in the coffin of something)

nail in the coffin of

An event, decision, action, etc., that can or will lead to the failure or cessation of something. The candidate's uncouth comment about the lower class was the final nail in the coffin of an already foundering campaign. That class action lawsuit could be a nail in the coffin of a company that has already seen its fair share of controversy.
See also: coffin, nail, of