A roundel in heraldry is a small disk used as a charge on a shield. In continental heraldry they are generally just termed roundels of such-and-such a colour, but in English heraldry special names are used for each one.

In the common colours:
A bezant is a roundel or (gold).
A plate is a roundel argent (silver).
A torteau is a roundel gules (red).
A hurt is a roundel azure (blue).
A pomeis is a roundel vert (green).
A pellet or ogress or gunstone is a roundel sable (black).

And with the rare colours:
A golpe is a roundel purpure (purple).
An orange is a roundel tenné (orange).
A guze is a roundel sanguine (maroon).

A roundel divided into a wavy white and blue representation of water is called a fountain. (In families called Sykes the fountain is termed a syke: one of those quaint prerogatives or affections that pop up in heraldry.)

A voided roundel (one with the centre cut out to leave only a ring) is termed an annulet.

Tiefling mentions that a torteau is also called a gout and a field semé (sewn or strewn) with them is called gouty. My source (Fox-Davies) doesn't mention this under roundels, but under semé discusses the goutte or drop; a field semé of gouttes is termed goutté or gutté and would look almost identical to a field semé of roundels. Once more, continental heraldry simply names the colour but British heraldry has special names: so goutté gules (red) is blazoned as goutté-de-sang (dropped with blood).

Also, a poem by Dorothy Parker:

She's passing fair; but so demure is she,
So quiet is her gown, so smooth her hair,
That few there are who note her and agree
She's passing fair.

Yet when was ever beauty held more rare
Than simple heart and maiden modesty?
What fostered charms with virtue could compare?

Alas, no lover ever stops to see;
The best that she is offered is the air.
Yet- if the passing mark is minus D-
She's passing fair.

Roun"del (?), n. [OF. rondel a roundelay, F. rondel, rondeau, a dim. fr. rond; for sense 2, cf. F. rondelle a round, a round shield. See Round, a., and cf. Rondel, Rondelay.]

1. Mus.

A rondelay.

"Sung all the roundel lustily."

Chaucer.

Come, now a roundel and a fairy song. Shak.

2.

Anything having a round form; a round figure; a circle.

The Spaniards, casting themselves into roundels, . . . made a flying march to Calais. Bacon.

Specifically: (a)

A small circular shield, sometimes not more than a foot in diameter, used by soldiers in the fourteenth and fifteenth centuries

. (b) Her.

A circular spot; a sharge in the form of a small circle

. (c) Fort.

A bastion of a circular form

.

 

© Webster 1913.