[The Colorful Etymology of 'Blue' and the Linguistic Mystery of 'Plum']-[The political, royal and obscene meanings of blue. The differences in ‘plumb’ and plum.’]

Grammar Girl Quick and Dirty Tips for Better Writing · B2 · 2025-10-14

📋 Summary

The Linguistic Spectrum of 'Blue' and the Versatility of 'Plum'

In this episode of Grammar Girl, Mignon Fogarty explores the surprisingly diverse origins of color-based idioms and clarifies the distinction between two homophonous, yet etymologically unrelated, uses of the word "plum."

The Many Shades of 'Blue'

The color blue permeates the English language with a vast array of meanings, often rooted in historical, medical, or cultural contexts:

Political Designations: While "red states" and "blue states" are standard in modern American discourse, this association is relatively recent. Fogarty notes that it wasn't until the 2000 presidential election that these colors became definitively linked to Republican and Democratic parties, respectively, following inconsistent usage by various TV networks since 1976.
Emotional and Physical States: To be "blue in the face" originates from the medical reality of oxygen deprivation, describing the exhaustion or frustration one feels when repeating oneself to no avail. Similarly, feeling "blue" to describe sadness has been documented since Chaucer in 1385.
Value and Nobility: The term "blue chip" stocks refers to high-value companies, a metaphor stemming from the early 20th century when blue poker chips represented the highest value. Conversely, "blue blood" denotes nobility, potentially linking to the visible veins in pale skin, the historical cost of blue dyes, or even medical conditions like agyria and methemoglobinemia.
Rare Phenomena: "Once in a blue moon" refers to a rare event. Scientifically, a "seasonal blue moon" is the fourth full moon in an astronomical season, while a "monthly blue moon" is the second full moon in a single month.
Obscenity and Restriction: The term "blue movie" and "blue humor" denote obscenity, with murky origins potentially linked to prisoners’ uniforms or French book covers. In contrast, "blue laws" refer to puritanical regulations restricting activities on Sundays.
Religious Symbolism: The blue and white stripes of the Israeli flag, which also influence Hanukkah imagery, are derived from the tzitzit (fringes of a prayer shawl), representing the blue thread mandated by the Torah.

The Tale of Two 'Plums'

Fogarty clarifies the confusion between the intensifier "plum" and the fruit "plum," emphasizing that they share no etymological history.

Plum (with a 'B'): Derived from the Latin plumbum (lead), this word is related to "plumbing." It stems from a "plumb line," a tool used by carpenters to ensure structures are vertical. By 1588, it evolved into an intensifier meaning "completely" or "absolutely," as seen in phrases like "plum crazy" or "plum out of." It is crucial to remember the silent 'b' when using this as an intensifier.
Plum (the fruit): Originating from the Old English plume and Latin prunum, this word refers to a desirable prize. The phrase "a plum job assignment" evokes the imagery of Little Jack Horner, who pulled a "plum" (the best part) out of a pie.

Familects: A Linguistic Legacy

The episode concludes with a listener-submitted "familect"—a private family language. The listener shared that her family uses the phrase "strong to the binnage" (a mishearing of Popeye’s "strong to the finish") to describe physical or metaphorical strength. This anecdote highlights how language evolves through misinterpretation and shared cultural experiences, solidifying into meaningful, localized expressions within families.

🎯Key Sentences

But these designations are newer than you might think.

When someone does something until she is blue in the face, she's feeling frustrated and exasperated.

Unfortunately, in this case, the room will probably stay messy.

Well, at the turn of the 20th century, blue poker chips were very valuable.

The origin is uncertain, but it may refer to a plate that was actually blue.

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📝Key Phrases

blue in the face

blue chip

blue plate special

blue blood

once in a blue moon

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📖 Transcript

Grammar Girl here.

I'm Mignon Fogarty, your friendly guide to the English language.

Today we're going to talk about blue idioms and then about the difference between being plum out of something and getting a plum job assignment.

In this segment, we'll take a look at phrases that use the color blue.

First up is politics.

These days in the United States, we hear about red states and blue states, where red refers to states that reliably vote for Republicans and blue refers to states that reliably vote for Democrats.

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