la·​cu·​na lə-ˈkü-nə How to pronounce lacuna (audio) -ˈkyü- How to pronounce lacuna (audio)
plural lacunae lə-ˈkyü-(ˌ)nē How to pronounce lacuna (audio) -ˈkü-ˌnī How to pronounce lacuna (audio) also lacunas lə-ˈkü-nəz How to pronounce lacuna (audio)
: a blank space or a missing part : gap
the evident lacunae in his storyShirley Hazzard
also : deficiency sense 1
despite all these lacunae, those reforms were a vast improvement New Republic
: a small cavity, pit, or discontinuity in an anatomical structure
lacunar adjective
or less commonly lacunate
lə-ˈkü-nət How to pronounce lacuna (audio)

Did you know?

If you find yourself drawing a blank when it comes to the definition of lacuna, it might help to imagine drawing water instead, ideally from a lake or lagoon. Lacuna, lake and lagoon all come ultimately from lacus, the Latin word for “lake.” Latin speakers modified lacus into lacuna to form a word meaning “pit,” “gap,” or “pool.” When English speakers borrowed the term in the 17th century, they used it to refer to a figurative gap in or missing portion of something, such as information or text. (Note that lacuna comes with two plural options: the Latin lacunae \luh-KYOO-nee\ or \luh-KOO-nye\ or the anglicized lacunas \luh-KOO-nuz\.) Lagoon, meanwhile, hewed closer to the Latin lacuna, referring first to a shallow sound, channel, or pond near or connected to a larger body of water, and later to a shallow artificial pool or pond.

Examples of lacuna in a Sentence

She found a lacuna in the historical record. attributes many of the nation's problems to a lacuna of leadership at the top
Recent Examples on the Web Among the problems that arise from this lacuna of information is that even the administration was unable to examine the plaintiffs’ purported issues with the program. Ryann Liebenthal, The New Republic, 9 May 2023 The lacuna extends beyond health research. Amy Yee, Scientific American, 8 July 2021 Nor is that the only lacuna. Benjamin Nugent, Harper's Magazine, 27 Apr. 2021 Yet surveying this landscape reveals a curious lacuna: software criticism, in which a piece of software is subjected to critical analysis. WIRED, 23 Feb. 2023 Ta-Nehisi Coates, in a devastating essay in the show’s catalogue, fills in the lacuna with his well-known, scorching pessimism about white mind-sets. Peter Schjeldahl, The New Yorker, 22 Feb. 2021 Data sets, some spanning decades, now feature a lacuna. Boyce Upholt, WIRED, 19 Nov. 2022 Of course, the big lacuna in deterrence theory is how to deter the idiot or, say, the leader who badly understands his own position. WSJ, 4 Nov. 2022 This lacuna reflects a widespread documentary practice that’s also a conventional lapse in aesthetic judgment. Richard Brody, The New Yorker, 8 Apr. 2022

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'lacuna.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


Latin, pool, pit, gap — more at lagoon

First Known Use

1652, in the meaning defined at sense 1

Time Traveler
The first known use of lacuna was in 1652


Dictionary Entries Near lacuna

Cite this Entry

“Lacuna.” Dictionary, Merriam-Webster, Accessed 28 May. 2024.

Medical Definition


la·​cu·​na lə-ˈk(y)ü-nə How to pronounce lacuna (audio)
plural lacunae -ˈkyü-(ˌ)nē How to pronounce lacuna (audio) -ˈkü-ˌnī How to pronounce lacuna (audio) also lacunas -ˈk(y)ü-nəz How to pronounce lacuna (audio)
: a small cavity, pit, or discontinuity in an anatomical structure: as
: one of the follicles in the mucous membrane of the urethra
: one of the minute cavities in bone or cartilage occupied by the osteocytes
lacunar adjective

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