The envoy (or envoi) is typically a short stanza that ends a longer poem such as a sestina or ballad. It comes from the French meaning ‘to send forth’ so it typically addresses a particular person or sums up the previous stanzas. The last 3 lines of a sestina is an example of an envoy stanza.

Example of an Envoy

Ballade of Modest Confession
BY HILAIRE BELLOC

My reading is extremely deep and wide;   
And as our modern education goes—
Unique I think, and skilfully applied   
To Art and Industry and Autres Choses
Through many years of scholarly repose.   
But there is one thing where I disappoint   
My numerous admirers (and my foes).   
Painting on Vellum is my weakest point.

I ride superbly. When I say I ‘ride’
The word’s too feeble. I am one of those   
That dominate a horse. It is my pride
To tame the fiercest with tremendous blows
Of heel and knee. The while my handling shows   
Such lightness as a lady’s. But Aroint   
Thee! Human frailty with thy secret woes!   
Painting on Vellum is my weakest point.

Painting on Vellum: not on silk or hide   
Or ordinary Canvas: I suppose
No painter of the present day has tried   
So many mediums with success, or knows   
As well as I do how the subject grows
Beneath the hands of genius, that anoint
With balm. But I have something to disclose—
Painting on Vellum is my weakest point.

Envoi
Prince! do not let your Nose, your royal Nose,   
Your large imperial Nose get out of Joint.
For though you cannot touch my golden Prose,   
Painting on Vellum is my weakest point.

Source: Complete Verse (1970)