[1] : The Collaborative International Dictionary of English v.0.48

intercalary \inter"calary\ ?; 277, a. l. intercalaris,
   intercalarius: cf. f. intercalaire. see intercalate.
   1913 webster
   1. chron. inserted or introduced among others in the
      calendar; as, an intercalary month, day, etc.; -- now
      applied particularly to the odd day feb. 29 inserted in
      the calendar of leap year. see bissextile, n.
      1913 webster

   2. introduced or inserted among others; additional;
      supernumerary. "intercalary spines." --owen.
      1913 webster

            this intercalary line . . . is made the last of a
            triplet.                              --beattie.
      1913 webster

   intercalary day med., one on which no paroxysm of an
      intermittent disease occurs. --mayne.
      1913 webster
see also:
intercalate bissextile intercalary day 

[2] : WordNet (r) 2.0

intercalary
     adj : added or having an addition to make the calender year
           correspond to the solar year; "feb. 29 is an
           intercalary day"; "leap year is an intercalary year"

Intercalary >> I Words
Intercalary, definition of term: Intercalary
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