The noun flag has 7 senses (first 2 from tagged texts)
1. (26) flag -- (emblem usually consisting of a rectangular piece of cloth of distinctive design)
2. (1) iris, flag, fleur-de-lis, sword lily -- (plants with sword-shaped leaves and erect stalks bearing bright-colored flowers composed of three petals and three drooping sepals)
3. flag, signal flag -- (a rectangular piece of fabric used as a signalling device)
4. masthead, flag -- (a listing printed in all issues of a newspaper or magazine (usually on the editorial page) that gives the name of the publication and the names of the editorial staff, etc.)
5. pin, flag -- (flagpole used to mark the position of the hole on a golf green)
6. flag, flagstone -- (stratified stone that splits into pieces suitable as paving stones)
7. flag -- (a conspicuously marked or shaped tail)
Overview of verb flag
The verb flag has 5 senses (first 2 from tagged texts)
1. (1) flag -- (communicate or signal with a flag)
2. (1) flag -- (provide with a flag; "Flag this file so that I can recognize it immediately")
3. sag, droop, swag, flag -- (droop, sink, or settle from or as if from pressure or loss of tautness)
4. flag -- (decorate with flags; "the building was flagged for the holiday")
5. ease up, ease off, slacken off, flag -- (become less intense)