Deadpan

Deadpan is a form of comic delivery in which humor is presented without a change in emotion or body language. It is usually spoken in a casual, monotone, or cantankerous voice, and expresses a calm, sincere, or grave demeanor, often in spite of the ridiculousness of the subject matter. This delivery is also called dry humor or dry wit, when the in...
Found on http://en.wikipedia.org/wiki/Deadpan

deadpan

expressionless adjective deliberately impassive in manner; `deadpan humor`; `his face remained expressionless as the verdict was read`
Found on https://www.encyclo.co.uk/local/20974

Deadpan

A specific type of comedic device in which the performer assumes an expressionless (deadpan) quality to her/his face demonstrating absolutely no emotion or feeling. This was a trademark of Buster Keaton's comedic form
Found on http://www.allmovie.com/glossary/term/deadpan

deadpan

[adj] - deliberately impassive in manner 2. [adv] - without betraying any feeling
Found on http://www.webdictionary.co.uk/definition.php?query=deadpan
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