Intercalary in a sentence as an adjective

In the library, intercalary days are just their own month.

We could go partial French Revolutionary, and have 36 10-day weeks at +3-1+3-3, plus an intercalary partial week at -5 or -6.

Macrobius describes a further refinement wherein, for 8 years out of 24, there were only three intercalary years, each of 377 days.

These intercalary days will be holidays for visiting family, and we'll shift them and New Years so that they will occur in the spring, where weather is generally more conducive to travel.

Intercalary definitions

adjective

having a day or month inserted to make the calendar year correspond to the solar year: "Feb. 29 is an intercalary day"; "a leap year is an intercalary year"