Dead sure
Really and dead sure are semantically related. in definitely topic. In some cases you can use "Really" instead an adverb phrase "Dead sure".
Really
Really adverb - In actual fact.
Mutual synonyms
Cite this Source
Really and Dead sure. (2016). Retrieved 2026, July 22, from https://thesaurus.plus/related/dead_sure/really
Dead sure & Really. N.p., 2016. Web. 22 Jul. 2026. <https://thesaurus.plus/related/dead_sure/really>.
Really or Dead sure. 2016. Accessed July 22, 2026. https://thesaurus.plus/related/dead_sure/really.
Google Ngram Viewer shows how "dead sure" and "really" have occurred on timeline