What does flag mean?
A flag is a piece of cloth, usually rectangular and fixed at one edge to a pole, that serves as a visible emblem or signal. Most familiarly, nations and organizations use flags as symbols of identity, flown at public buildings, carried in ceremonies, and raised or lowered to mark respect or mourning. Flags also function practically: they signal hazards on beaches, mark positions on maps, and indicate waiting taxis. As a verb, 'flag' has two well-established meanings: to mark something for attention — increasingly common in digital life, where users flag inappropriate content or flag emails for follow-up — and to grow tired or weak, as when enthusiasm or energy flags. The word carries connotations of both identity and attention: raising a flag declares allegiance, while red-flagging warns of danger. Its versatility across physical and figurative senses makes it a staple of everyday English.
A piece of cloth attached by one edge to a pole or rope, used as a national or organizational emblem or as a signal.
"The embassy flew the national flag above its entrance."
To mark or draw attention to something, often for later review; or to become weak or tired.
"She flagged the email so she could reply to it after lunch."
Regular plural formation.
"Flags from every participating nation lined the stadium."
The word 'flag' may descend from an old word for a slab of stone — the same root that gave us 'flake'.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of flag
The noun 'flag' emerged in English in the 16th century, likely from an earlier word for a piece of cloth or a flat surface; some etymologists connect it to Old Norse 'flaga', meaning a slab or flat layer, a root also reflected in 'flake'. Its use as a verb meaning to droop or lose energy appeared around the same period, though its exact origin is uncertain. Related Germanic words with similar forms exist in Dutch and German, but precise relationships are debated.
Related word forms
How flag is actually used
As a verb, 'flag' spans two distinct meanings: marking or signaling (often in digital contexts, e.g. flagging a comment) and losing strength or momentum. Register is neutral across uses.
Easily confused with flag
'Flak' refers to anti-aircraft fire or strong criticism, whereas 'flag' is a cloth symbol or a verb meaning to mark or weaken.