Calendar Day Legal Definition: In some jurisdictions, a period of time from midnight to midnight. In others, a full 24 hour period (eg. 3 am to 3 am). Related Terms: Day , Clear Days , Calendar Month , Calendar Year , Calendar Quarter The 2010 General Construction Law of New York, Article 2, §19, defines a calendar day as follows:"A calendar day includes the time from midnight to midnight. "Sunday or any day of the week specifically mentioned means a calendar day."This interpretation was reiterated in the 1940 case, Lanni v Grimes, in which Justice Lapham of the New York Supreme Court for Monroe County had before him the 1940 version of that statutory definition and wrote:"The General Construction Law (of New York) defines a calendar day as including the time from midnight to midnight. Nevertheless, courts will take notice of the fractions of a day, when there are conflicting rights, for the determination of which it is necessary for them to do so."As a general rule the court does not inquire into the fractions of a day, except for the purpose of guarding against injustice...."The law does not regard fractions of a day, except in cases where the hour itself is material, as in the case where priority of judgments is in question."However, in Guillory, Justice Blanche of the the Supreme Court of Louisiana preferred a definition of "a full 24-hour period" although it was opined in the context of a specific statute:"[T]he term calendar days is meant to indicate a full twenty-four hour period....”REFERENCES:Duhaime, Lloyd, Legal Definition of Calendar Month Duhaime, Lloyd, Legal Definition of Calendar Quarter Duhaime, Lloyd, Legal Definition of Calendar Week Duhaime, Lloyd, Legal Definition of Calendar Year Guillory v Department of Transport, 450 So. 2d 1305 (Louisiana, 1984) Kuznitsky v Murphy, 44 N.E. 2d 893 (1942, Illinois) Lanni v Grimes, 18 N.Y.S. 2d 322 (1940) Unless otherwise noted, this page was written by Lloyd Duhaime of Duhaime.org Always looking up definitions? Save time with our search provider (modern browsers only) If you find an error or omission in Duhaime's Law Dictionary, or if you have suggestion for a legal term, we'd love to hear from you!