Answer: dick

AnswerCrossword Clue
DICKWord each theme entry ends with a synonym for
DICKNixon.
DICKDetective: Slang.
DICKSleuth of a sort.
DICKMerriwell.
DICKOne of a well-known trio.
DICKHotel cop
DICKTracy or Cavett
DICKVan Dyke
DICKCavett
DICKTess's bridegroom
DICKButton on the ice
DICKFormer White House nickname
DICKTracy of the comics
DICKAuthor Philip K. ...
DICKGumshoe.
DICK-- Van Dyke
DICK"Tricky" White House nickname
DICKGregory or Francis
DICK"Tricky" nickname
DICK... Van Dyke
DICKPolice detective
DICK.... Van Dyke
DICK"Tricky ..." (presidential nickname)
DICKVeep between Al and Joe
DICKPresidential nickname
dickto copulate with
dickdetective
dickpenis
dickmale given name, form of Richard
DICKNixon nickname
DICKClark or Tracy
DICKAuthor Philip K.
DICKTracy
DICKEither portrayer of TV's Darrin Stevens
DICKVonnegut's "Deadeye ..."
DICKButton or Butkus
DICKClark or Cheney
DICKActor Van Dyke
DICK1999 movie about Nixon