quarterly

from The American Heritage® Dictionary of the English Language, 5th Edition.

• adjective Made up of four parts.
• adjective Being one of four parts.
• adjective Occurring or appearing at three-month intervals.
• adjective Heraldry Having four sections. Used of a shield.
• noun A publication issued regularly every three months.
• noun An examination given regularly every three months in some colleges.
• adverb In or by quarters.

from The Century Dictionary.

• In quarters; by quarters.
• Once in a quarter of a year: as, the returns are made quarterly.
• In heraldry: Arranged according to the four quarters of the shield.
• Arranged according to quartering, even when more than four divisions exist: as, he bears quarterly of twelve. Compare quartering, 4.
• Containing or consisting of a fourth part.
• Recurring at the end of every quarter of the year: as, quarterly payments of rent; a quarterly visitation or examination.
• noun A publication or literary periodical issued once every three months.

from the GNU version of the Collaborative International Dictionary of English.

• adverb By quarters; once in a quarter of a year.
• adverb (Her.) In quarters, or quarterings; ; in four or more parts; -- said of a shield thus divided by lines drawn through it at right angles.
• adjective Containing, or consisting of, a fourth part.
• adjective Recurring during, or at the end of, each quarter
• noun A periodical work published once a quarter, or four times in a year.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• adjective Occurring once every quarter year (three months).
• adverb Once every quarter year (three months).
• noun A periodical publication that appears four times per year.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• adjective of or relating to or consisting of a quarter
• noun a periodical that is published every quarter (or four issues per year)
• adverb in three month intervals
• adverb in diagonally opposed quarters of an escutcheon