Definition from Wiktionary, the free dictionary
- (hunting) The rigid pose a hunting dog assumes when pointing out game to a hunter.
- The judge at the dog show took points off the Irish setter's dead set because its right ear twitched a few times.
- A fixed or stationary condition arising from obstacle or hindrance; a deadlock.
- to be at a dead set
- (figuratively) By extension, a determined effort.
- I might not graduate first in my class, but I'll make a dead set at it.
- unswervingly dedicated; resolutely determined
- If John is dead set on marrying Catherine, his parents' objection will only provoke a falling out.
- The governor is dead set against the concealed weapons permit legislation and will veto it even if it costs her the re-election.