[1] : WordNet (r) 2.0

deadpan
     adj : deliberately impassive in manner; "deadpan humor"; "his face
           remained expressionless as the verdict was read" syn:
           expressionless, impassive, poker-faced, unexpressive
     adv : without betraying any feeling; "she told the joke deadpan"
see also:
expressionless impassive poker-faced unexpressive 

[2] : Moby Thesaurus II by Grady Ward, 1.0

22 moby thesaurus words for "deadpan":
   blank, cold-bloodedly, coldheartedly, coldly, dispassionately,
   empty, expressionless, fishy, glassy, heartlessly, impassive,
   in cold blood, inexpressive, poker-faced, spiritlessly,
   unemotionally, unexpressive, unfeelingly, unpassionately, vacant,
   with dry eyes, wooden

Deadpan >> D Words
Deadpan, definition of term: Deadpan
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