in·​ter·​ca·​late in-ˈtər-kə-ˌlāt How to pronounce intercalate (audio)
intercalated; intercalating

transitive verb

: to insert (something, such as a day) in a calendar
: to insert or position between or among existing elements or layers
intercalation noun

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Intercalate was formed from the Latin prefix inter-, meaning "between" or "among," and the Latin verb calāre, meaning "to proclaim" or "to announce." It was originally associated with proclaiming the addition of a day or month in a calendar. An instance of intercalation occurred in the earliest versions of the Roman calendar, which originally consisted of 304 days and 10 months and was determined by the lunar cycle (the remaining 61.25 days of winter were apparently ignored). According to some Roman legends, it was Numa Pompilius, the second king of Rome, who intercalated the months January and February. Eventually, the word's use broadened to include other instances of introducing new elements or layers into a preexisting system.

Choose the Right Synonym for intercalate

introduce, insert, insinuate, interpolate, intercalate, interpose, interject mean to put between or among others.

introduce is a general term for bringing or placing a thing or person into a group or body already in existence.

introduced a new topic into the conversation

insert implies putting into a fixed or open space between or among.

inserted a clause in the contract

insinuate implies introducing gradually or by gentle pressure.

insinuated himself into the group

interpolate applies to the inserting of something extraneous or spurious.

interpolated her own comments into the report

intercalate suggests an intrusive inserting of something in an existing series or sequence.

new chapters intercalated with the old

interpose suggests inserting an obstruction or cause of delay.

interpose barriers to communication

interject implies an abrupt or forced introduction.

interjected a question

Examples of intercalate in a Sentence

between the recipes for hearty peasant dishes, the author intercalates fond reminiscences of her year in the French countryside

Word History


borrowed from Latin intercalātus, past participle of intercalāre "to insert (a day or month) into the calendar," from inter- inter- + calāre "to announce, proclaim" — more at low entry 3

Note: For the use of the verb calāre in the Roman management of the calendar see etymology and note at calends.

First Known Use

1603, in the meaning defined at sense 1

Time Traveler
The first known use of intercalate was in 1603


Dictionary Entries Near intercalate

Cite this Entry

“Intercalate.” Dictionary, Merriam-Webster, Accessed 4 Oct. 2023.

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