Boredom, or ennui, (AUDIO: The Lamentation Cipher [+]Error: Code 2 - no data stored in variables, cache or SMW.) was an emotion.
The Doctor frequently claimed that he had left Gallifrey because he was bored. (TV: The War Games [+]Terrance Dicks and Malcolm Hulke, Doctor Who season 6 (BBC1, 1969)., Voyage of the Damned [+]Russell T Davies, Doctor Who Christmas Special 2007 (BBC One, 2007)., Heaven Sent [+]Steven Moffat, Doctor Who series 9 (BBC One, 2015).) However, Davros believed that this was a lie. (TV: The Witch's Familiar [+]Steven Moffat, Doctor Who series 9 (BBC One, 2015).) The Twelfth Doctor confessed it was a lie while inside his confession dial. (TV: Heaven Sent [+]Steven Moffat, Doctor Who series 9 (BBC One, 2015).) The First and Fourth Doctors admitted that there several other "pressing reasons" at the time. (TV: Twice Upon a Time [+]Steven Moffat, Doctor Who Christmas Special 2017 (BBC One, 2017)., Logopolis [+]Christopher H. Bidmead, Doctor Who season 18 (BBC1, 1981).)
Whilst in a dream, created by the Dream Lord, of Upper Leadworth in 2022, the Eleventh Doctor asked Amy Pond and Rory Williams to "stave off the, you know...", to which Amy added "boredom" before the Doctor finished "self harm". Rory answered that they relaxed. (TV: Amy's Choice [+]Simon Nye, Doctor Who series 5 (BBC One, 2010).)
Shortly before his death and regeneration into the Twelfth Doctor, the Doctor joked that as Daleks spoke very slowly, he would probably "die of boredom" before they finally shot him. (TV: The Time of the Doctor [+]Steven Moffat, Doctor Who Christmas Special 2013 (BBC One, 2013).)
Things the Doctor found boring included the planet Calufrax, (TV: The Pirate Planet [+]Douglas Adams, Doctor Who season 16 (BBC1, 1978).) studying Druidic lore, (TV: The Stones of Blood [+]David Fisher, Doctor Who season 16 (BBC1, 1978).) the Vulgar End of Time, (AUDIO: The One Doctor [+]Gareth Roberts and Clayton Hickman, Main Range (Big Finish Productions, 2001).) the two weeks he ran Taunton in the 18th century, (PROSE: The Highest Science [+]Gareth Roberts, Virgin New Adventures (Virgin Books, 1993).) sitting watching the cubes all day, (TV: The Power of Three [+]Chris Chibnall, Doctor Who series 7 (BBC One, 2012).) Earth in 2105, (TV: The End of the World [+]Russell T Davies, Doctor Who series 1 (BBC One, 2005).) queuing, golf and taking the bins out. (COMIC: Epilogopolis [+]Error: Code 2 - no data stored in variables, cache or SMW.)
Ace called Perivale "the boredom capital of the universe". (TV: Survival [+]Rona Munro, Doctor Who season 26 (BBC1|BBC1]], 1989).)
Gilgamesh believed that danger staved off the boredom of life. He scoffed at Enkidu's claim that there were worse things in life than boredom. (PROSE: Timewyrm: Genesys [+]John Peel, Virgin New Adventures (Virgin Books, 1991).)
Morella Wendigo claimed to be bored of Tamsin Drew within seconds. (AUDIO: Nevermore [+]Alan Barnes, Eighth Doctor Adventures (Big Finish Productions, 2010).)
Jack Harkness thought that the Arcans were boring. (TV: Cyberwoman [+]Chris Chibnall, Torchwood series 1 (BBC Three, 2006).)
Joanna Harris, a vampire, said that she had not been bored since the invention of the Internet. (PROSE: Vampire Science [+]Kate Orman and Jonathan Blum, BBC Eighth Doctor Adventures (BBC Books, 1997).)
Das, a Neanderthal, did not understand why humans hated boredom. (PROSE: Only Human [+]Gareth Roberts, BBC New Series Adventures (BBC Books, 2005).)
The New Earth Republic was so successful that boredom was the only problem. (PROSE: Synthespians™ [+]Craig Hinton, BBC Past Doctor Adventures (BBC Books, 2004).)
Bram and Gregor Van Baalen told their amnesiac brother Tricky he was an android as a joke to relieve their boredom. (TV: Journey to the Centre of the TARDIS [+]Steve Thompson, Doctor Who series 7 (BBC One, 2013).)
The Toymaker spent centuries wandering the Earth sampling its games (PROSE: The Nightmare Fair [+]Graham Williams, adapted from The Nightmare Fair, Target Missing Episodes (Target Books, 1989).) and luring people back to the Toyroom because he was bored. (TV: The Celestial Toymaker [+]Brian Hayles, Doctor Who season 3 (BBC1, 1966)., COMIC: The Greatest Gamble [+]John Peel, DWM backup comic stories (Marvel Comics, 1981). Pages 40-42.)