1
: a group or set of 10
It isn't to be done in a day of course, nor yet in a century, —nor in a decade of centuries …—Anthony Trollope
: such as
a
: a period of 10 years
has been teaching for over a decade
the decade of the twenties
b
Roman Catholicism
: a division of the rosary that consists primarily of 10 Hail Marys
2
mathematics
: a ratio of 10 to 1 : order of magnitude
Cite this Entry
“Decade.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/decade. Accessed 1 Nov. 2026.
Copy CitationLove words? Need even more definitions?
Merriam-Webster unabridged
