A showmance is a romance between people working on the same show, whether cast members of a play or contestants sharing a reality-television house. The word is a neat blend of show and romance, and it comes with a raised eyebrow: nobody is quite sure whether the feelings will survive the final curtain, or whether they were partly for the cameras.
The word researcher Barry Popik traced printed examples back to 1999, when a theatre review used show-mance for actors falling for fellow actors. By 2004 American newspapers were applying it to reality contestants, sometimes suggesting a romance had been staged for extra screen time. A reality-show alumnus later claimed to have coined the term and filed a trademark for it in 2006, although the theatre crowd had clearly got there first, and the trademark is now listed as dead. Long rehearsals, late nights and shared nerves were producing showmances long before anyone had a name for them.