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REFERENCE

flag

n. · v.
US //ˈfɫæɡ// UK //flˈæɡ// flag
  1. 1 symbolic cloth (n.)
    A2 Elementary

    a piece of cloth with a special design that represents a country, group, or organization.

    a piece of fabric, usually rectangular, bearing a distinctive design used as a symbol, signaling device, or emblem of a nation or entity.

    Example

    The crowd waved their national flags during the opening ceremony of the games.

    Example

    The protocol for displaying the national flag requires it to be illuminated if flown after sunset.
  2. 2 a warning or indicator (n.)
    B1 Intermediate

    a sign or signal that shows something needs attention or that a problem exists.

    a symbolic or digital indicator used to draw attention to a specific item, condition, or potential problem.

    Example

    The teacher put a red flag next to the student's name because he missed too many classes.

    Example

    The software developer added a flag to the code to alert the system whenever a user entered an invalid password.
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  1. 3 to mark for attention (v.)
    B2 Upper Intermediate

    to mark something so that you or someone else will notice it later.

    to identify or mark an item for subsequent attention or treatment.

    Example

    I've flagged the most important emails so I can reply to them first tomorrow morning.

    Example

    The audit flagged several inconsistencies in the financial reports that required immediate clarification from the accounting department.

    Usage

    often used with 'up' in British English
  2. 4 to signal to stop (v.)
    B1 Intermediate

    to wave at a driver to make them stop their vehicle.

    to signal a vehicle to stop, typically by waving one's hand or a physical flag.

    Example

    We had to flag down a taxi because it was raining and we didn't have an umbrella.

    Example

    The stranded motorist managed to flag down a passing truck just as his phone battery died.

    Usage

    commonly used as 'flag down'
  3. 5 to become tired (v.)
    C1 Advanced Literary

    to become tired, weak, or less interested in something.

    to decline in strength, vigor, or interest; to become languid or feeble.

    Example

    By the end of the long meeting, everyone's energy began to flag.

    Example

    Despite his initial enthusiasm for the project, his interest began to flag when the technical challenges became increasingly repetitive.
  4. 6 a flat stone (n.)
    C2 Proficiency Technical

    a large, flat stone used for making paths or floors.

    a hard, flat stone used for paving slabs; a shortened form of 'flagstone'.

    Example

    The garden path was made of old grey flags that had grown moss over the years.

    Example

    The restoration committee insisted on sourcing authentic limestone flags to maintain the historical integrity of the cathedral floor.
  5. 7 a plant (n.)
    C2 Proficiency Technical Biology

    a type of plant with long, sword-shaped leaves, often a kind of iris.

    any of various plants with sword-shaped leaves, particularly those in the iris family.

    Example

    Yellow flags grew thickly along the edge of the river.

    Example

    The marshy banks were dominated by Iris pseudacorus, commonly known as the yellow flag, which provides essential habitat for local insects.
Etymology 1

From Middle English flag, flagge (“flag”), further etymology uncertain. Perhaps from or related to early Middle English flage (name for a baby's garment) and Old English flagg, flacg (“cataplasm, poultice, plaster”). Or, perhaps ultimately imitative, or otherwise drawn from Proto-Germanic flaką (“something flat”), from Proto-Indo-European pleh₂- (“flat, broad, plain”), referring to the shape. Germanic cognates include Saterland Frisian Flaage (“flag”), West Frisian flagge (“flag”), Dutch vlag (“flag”), German Flagge (“flag”), Swedish flagga (“flag”), Danish flag (“flag, ship's flag”). Compare also Middle English flacken (“to flutter, palpitate”), Swedish dialectal flage (“to flutter in the wind”), Old Norse flögra (“to flap about”). Akin to Old High German flogarōn (“to flutter”), Old High German flogezen (“to flutter, flicker”), Middle English flakeren (“to move quickly to and fro”), Old English flacor (“fluttering, flying”). More at flack, flacker.

Etymology 2

Perhaps from a variant of flack (“to hang loose”), from Middle English flacken; or perhaps from Old Norse. Compare Middle Dutch flaggheren, vlaggheren (“to droop, flag”).

Etymology 3

From Middle English flagge, of uncertain origin, perhaps from North Germanic; compare Danish flæg (“yellow iris”). Or, possibly from sense 1, referring to its motion in the wind. Compare also Dutch vlag.

Etymology 4

From Middle English flag, flagge, probably of Scandinavian/North Germanic origin; compare Icelandic flag.

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