Third Wheel and Fifth Wheel – Meaning & Origin

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Danielle McLeod

Danielle McLeod is a highly qualified secondary English Language Arts Instructor who brings a diverse educational background to her classroom. With degrees in science, English, and literacy, she has worked to create cross-curricular materials to bridge learning gaps and help students focus on effective writing and speech techniques. Currently working as a dual credit technical writing instructor at a Career and Technical Education Center, her curriculum development surrounds student focus on effective communication for future career choices.

The idiomatic expression third wheel describes a person who tags along with a couple or group, often feeling out of place or unnecessary. While the phrase can imply that the person is unwanted, it can also be used in a more lighthearted manner.

On the other hand, fifth wheel is less commonly used to describe someone who feels extra in a group, especially when two couples are involved. However, most people know the term third wheel and prefer using it, as fifth wheel can create confusion.

Read on to see how to use the idiomatic term third wheel properly and why you should avoid using fifth wheel as a substitute.

Understanding Third Wheel Meaning

Third Wheel and Fifth Wheel – Meaning Origin

The term third wheel refers to someone who feels unnecessary or out of place in a group, often when the group is primarily composed of couples. Though the term usually applies to situations involving a couple plus one additional person, it can also extend to larger groups where someone still feels awkward or out of place.

For example:

  • I hate going to the movies with them; even though they invited me, I always feel like the third wheel.
  • After my date was canceled, I decided not to go on the couples’ cruise; I would’ve just been the third wheel among the other pairs.

Third wheel doesn’t always carry a negative connotation. It’s often used lightheartedly to acknowledge an imbalance in the group, even when the “extra” person is actually welcome.

For example:

  • Hey everyone! I’m your tour guide today. Are you ready to have me as your third wheel?
  • Our third wheel is here to make sure everyone gets home safe tonight!

The term fifth wheel can technically mean the same thing, but it’s rarely used in this context. Third wheel is the more commonly recognized phrase for describing someone who feels extraneous in a group setting.

Third Wheel Idiom Origins

Third Wheel Ngram
Literal and Figurative Uses of Third and Fifth Wheel

The origins of the terms “third wheel” and “fifth wheel” are a subject of interest, especially their literal meanings. Historically, a “fifth wheel” was an extra wheel carried on the back of a four-wheel horse-drawn wagon or carriage. According to Brewer’s Dictionary of Phrase and Fable, first published in 1894, carrying an extra wheel was seen as cumbersome and awkward in the 1600s but could be a lifesaver in emergencies.

In the 17th century, two-wheel carriages, known as one-horse shays, were also common. This makes it plausible that a “third wheel” could have been carried as a spare for these smaller carriages.

While there’s no definitive record of when these terms started being used metaphorically, it seems that “third wheel” became popular in the social context during the latter half of the 20th century. Before that, both “third wheel” and “fifth wheel” were probably referenced more in their literal sense, especially given that the “fifth-wheel camper” was invented in the early 1900s.

Let’s Review

While it’s hard to pinpoint the exact origins of the term third wheel in its figurative sense, we do know that carrying a spare wheel—either a fifth or third—was a common practice for four and two-wheeled carriages, especially in the 1600s. This historical context of carrying an extra but somewhat awkward item has evolved into the modern-day term we use to describe someone who feels like the odd one out in a group.

Want to have more idioms in your arsenal? Check out some others we covered: