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How I Met Your Mother S05E01, DefinitionsS05E01

How I Met Your Mother · Season 5

How I Met Your Mother season 5 episode 1: Definitions

Aired 21 September 200923 minRated TV-14

7.8TMDB · 39 votesMark watched

Where to watch How I Met Your Mother Season 5 in Australia

How I Met Your Mother season 5 is streaming in Australia on Disney+ (subscription, listed for the whole show). You can also buy it on Apple TV from $24.99 and Prime Video Store from $24.99.

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Availability checked 16 November 2026.

What happens in “Definitions”

After sharing a kiss at the beginning of the summer, Robin and Barney are unsure how to handle their mutual attraction. After some consideration they tell the gang they have decided to remain just friends, but secretly continue seeing each other. They are able to get away with their secret romance for a couple months, but are discovered when Ted, Marshall and Lily walk in on them together. They explain to the gang that they are happy with their casual relationship, and didn't want to complicate it by defining it. This is unacceptable to Lily, who pressures them to label their situation, and ultimately locks them in Robin's room to force them to address it. Meanwhile, Ted is anxious about his first days as a professor at Columbia, which is made worse when he shows up at the wrong class and starts his lecture.

Episode summary: TMDB.

Before you watch

  • It is the season premiere of season 5.
  • It runs about 23 minutes.
  • Directed by Pamela Fryman, written by Craig Thomas and Carter Bays.
  • TMDB users rate it 7.8 out of 10 (39 votes).

How I Met Your Mother trailer

The official trailer for the series (no preview of this episode has been published).

How I Met Your Mother trailerPlay video: How I Met Your Mother trailer

Cast and crew of this episode

Director
Pamela Fryman
Writers
Craig ThomasCarter Bays
Guest stars
Joe Manganiello as Brad MorrisDale E. Turner as CalzonettiKim Matula as Girl #1Abhi Sinha as Guy #2

Credits: TMDB.

More from How I Met Your Mother Season 5

Next · S05E02Double Date28 September 2009
  1. E01
  2. E02
  3. E03
  4. E04
  5. E05
  6. E06
  7. E07
  8. E08
  9. E09
  10. E10
  11. E11
  12. E12
  13. E13
  14. E14
  15. E15
  16. E16
  17. E17
  18. E18
  19. E19
  20. E20
  21. E21
  22. E22
  23. E23
  24. E24

Every episode of Season 5How I Met Your Mother episode guide

Episode names, air dates, runtimes, stills and ratings: TMDB. Air dates are the first broadcast anywhere; where it streams is our daily Australian check.