noun
twelvemonth
TWELV-munth/ˈtwelvmʌnθ/
A period of twelve months.
The lease runs for a full twelvemonth from today.

Etymology
Twelf and monað make a literal “twelve months.” A month originally measured the interval from one new moon to the next; the compound names the twelve-month span of a calendar year.
In context
when she hardly knew what money meant, she had promised Miss Macnulty seventy pounds for the first year, and seventy for the second, should the arrangement last longer than a twelvemonth.
More examples
- She spends a twelvemonth abroad before returning home.
- Two twelvemonths pass before the next family reunion.
- We have not seen each other for a twelvemonth.
Forms
twelvemonth · twelvemonths
Similar words
- year
- The usual modern word for a twelve-month period.