jams
noun
jams
1 American
[jamz]
/ dʒæmz /
noun
(used with a plural verb)
Jams
2
American
[jamz]
/ dʒæmz /
Trademark.
Usage
What does jams mean? Jams is a very informal word for pajamas—the clothes you wear to sleep in. The word jammies means the same thing but is more common. Terms like jammies, jams, and jam-jams are typically used by children, adults speaking to children, or people using childish words to be silly. A more common synonym for pajamas is p.j.’s, which is informal but not as informal as jammies. You could say that whatever clothes children change into before going to bed are their jams. Traditionally, though, the word refers to clothes that were specifically made and sold for sleeping in, typically consisting of soft, loose-fitting pants or shorts and a (sometimes matching) top. When adults use the words jams or jammies to refer to what they’re wearing, it’s usually to refer to clothes worn for sleeping, but not always. People sometimes use such terms to refer to the clothes they wear to lounge in, especially before bed, though the terms p.j.’s and pajamas are more likely to be used this way. In all cases, the word jams is used very informally. The word jams is also the plural of the noun jam or a present-tense version of the verb jam, both of which have many meanings. Example: OK, kids, time for bed—go brush your teeth and change into your dinosaur jams.
Etymology
Origin of jams
First recorded in 1965–70; by shortening
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
When agents moved in perfectly straight paths, they quickly formed dense clusters and traffic jams that halted progress.
From Science Daily • Apr. 15, 2026
An alternative to jams or jellies, we love spooning it onto bites of toasted bagels or hot buttered toast.
From Salon • Apr. 13, 2026
In December 2025, a large power outage in San Francisco led Waymo taxis to stop working around the city, causing huge traffic jams.
From BBC • Apr. 1, 2026
After dinner, Idle slung his Holy Grail-shaped bag — made by his daughter and lined with Spam-printed fabric — over his shoulder and left a voicemail for a friend he regularly jams with in L.A.
From Los Angeles Times • Mar. 23, 2026
“Now those jams are cool enough. You both get to filling up those jars.”
From "Root Magic" by Eden Royce
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
