What does decade mean?
A decade is a period of ten years, and it is one of the most widely used words for framing time in modern English. People speak of the past decade, the coming decade, or a decade of experience, using it to measure careers, trends, technologies, and historical change. By extension, decades are often treated as cultural units — "the sixties," "the eighties" — each carrying its own associations of style, politics, and mood. The word also has a narrower religious sense: a decade of the Rosary is a sequence of ten prayers counted on beads. Derived from the Greek "dekas" meaning a group of ten, via Latin and French, it belongs to a family of number-based words including decimal, decathlon, and decimate. Neutral in tone and precise in meaning, "decade" is indispensable for anyone discussing history, planning, or change across spans longer than a few years but shorter than a lifetime.
A period of ten consecutive years; by extension, any span marked off in tens of years, especially a calendar decade such as the 1970s.
"The museum's new exhibition traces a decade of scientific breakthroughs."
A set or group of ten items; specifically, a series of ten Hail Marys recited as one unit of the Rosary.
"She moved her fingers from bead to bead, completing another decade of the Rosary."
This sense is now largely confined to religious (Catholic) usage.
Regular plural. Note the distinction between "decades" (spans of ten years) and "decade's" (possessive); "decades of experience" is idiomatic, while "a decade's worth" uses the singular possessive.
"Over the decades, the small fishing village grew into a bustling port town."
The word "decade" comes from the Greek "dekas" — the same root that gives us "December," which was once literally the tenth month of the Roman year.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of decade
Decade derives from the Greek "dekas" (genitive "dekados"), meaning a group of ten, formed from "deka," the Greek word for ten. It passed into Latin as "decas" and reached English via French "décade" around the early seventeenth century. The same Greek root underlies related English words such as decimal, decathlon, and decimate, and it survives in "December," which was originally the tenth month of the early Roman calendar.
Related word forms
How decade is actually used
"Decade" is neutral in register and appears freely in formal and informal contexts alike. It is most often used with modifiers such as "the past," "the last," or "the next." When referring to calendar periods like "the 1990s," usage is well established; note that a decade technically begins at year one, though popular convention treats years ending in zero as its start.
Easily confused with decade
"Decayed" is the past tense of decay (having rotted), while "decade" is a period of ten years; they sound somewhat similar but are entirely unrelated in meaning.