noun Uncommon

placebo

pluh-SEE-boh

Placebo (noun) means a harmless substance given as if it were medicine, with no real active ingredient. Example: “Half the trial participants received the real drug and half got a placebo.”

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noun

A harmless substance given as if it were medicine, with no real active ingredient.

"Half the trial participants received the real drug and half got a placebo."

"Her headache improved even though she'd only taken a placebo."

How to use placebo

Learner’s notes

In plain EnglishA fake treatment used in medical trials to compare against the real drug, or more generally, something that works only because people believe it will.

Common pairings

placebo effect placebo-controlled trial sugar pill placebo

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C2 · Advanced serendipity Fortunate discoveries made entirely by accident.

Gen Z slang rizz Charm — the ability to attract a romantic interest.

B2 · Intermediate empathy The capacity to share another person’s feelings.

C1 · Advanced nonchalant Casually calm and relaxed; unconcerned.

Internet slang delulu Delusional — believing something against the odds.

Etymology nostalgia Greek nostos “return home” + algos “pain”.

C2 · Advanced serendipity Fortunate discoveries made entirely by accident.

Gen Z slang rizz Charm — the ability to attract a romantic interest.

B2 · Intermediate empathy The capacity to share another person’s feelings.

C1 · Advanced nonchalant Casually calm and relaxed; unconcerned.

Internet slang delulu Delusional — believing something against the odds.

Etymology nostalgia Greek nostos “return home” + algos “pain”.

Word forms

placebos plural, placeboes plural

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Half the trial participants received the real drug and half got a _____.

Etymology

From Latin placebo, "I will please," originally a line from a church prayer, later adopted into medicine for a "pleasing" but medically inactive treatment.

Origin: Latin

Rhymes for placebo

gazebo

See all rhymes for placebo →

Frequently asked questions

What does “placebo” mean?

The word “placebo” means a harmless substance given as if it were medicine, with no real active ingredient. In plain terms, a fake treatment used in medical trials to compare against the real drug, or more generally, something that works only because people believe it will.

How do you pronounce “placebo”?

“Placebo” is pronounced pluh-SEE-boh (/pləˈsi.boʊ/ in IPA).

How do you use “placebo” in a sentence?

Here is “placebo” used in a sentence: “Half the trial participants received the real drug and half got a placebo.”

What part of speech is “placebo”?

“Placebo” is a noun.

Where does the word “placebo” come from?

The word “placebo” comes from Latin. From Latin placebo, "I will please," originally a line from a church prayer, later adopted into medicine for a "pleasing" but medically inactive treatment.

Is “placebo” a common word?

“Placebo” is an uncommon word in modern English.

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