SHORT ANSWER
It's hard to tell as there is no context for the picture (e.g. is there text above or next to it?). The artist may not have intended any particular meaning, but I've listed some possibilities at the end of the long answer.
LONG ANSWER
There are many such strange illustrations in medieval manuscripts, especially in the margins (known as marginalia). In many (maybe most) cases we simply don't know what they mean, or even if they were supposed to mean anything at all. This from Collectors Weekly:
Though the meaning of specific images is still hotly debated, scholars
conjecture that marginalia allowed artists to highlight important
passages (or insert text that was accidentally left out), to poke fun
at the religious establishment, or to make pop-culture references
medieval readers could relate to. We’ll probably never understand all
the symbolism used in marginalia..
This article in History Today shows how even at least some contemporaries were baffled:
Debate over the purpose of these illustrations has continued, seemingly from the very beginning of their use. In the 12th century, St Bernard of Clairvaux wrote, What profit is there in those ridiculous monsters, in that marvellous and deformed beauty, that beautiful deformity? To what purpose are those unclean apes, those fierce lions, those monstrous centaurs, those half-men…
Kaitlin Manning notes that, previously,
...scholars were completely uninterested and wrote it [marginalia] off
as trivial or not meaning anything...It was only relatively recently,
due to the work of scholars like Michael Camille and Lillian Randall,
in particular, that marginalia became viewed as a genre worthy of
study...
Frances Spiegel says,
Sometimes the images depict stories associated with the text, but not necessarily directly related to it. In a time when so many people could not read, the pictures helped them understand and remember the text. Sometimes the pictures give a fascinating glimpse into the history of the region and the lives of people who created the text. Just occasionally they are there simply to delight the eye.
Illustrations were sometimes a commentary on the text but without knowing what that text is, interpretation of the illustration in the question above is all but impossible (if any interpretation was intended in the first place). However, I'll stick my neck out and venture some possibilities..
It is possible that the artist is referring (for some reason not evident here) to a high-born woman who enjoyed falconry/hawking (if the glove is intended to be a gauntlet). Another possible interpretation is that the part woman, part bird image is some kind of take on a siren. Or it is possible the artist did it just for the amusement of himself and / or the reader as there seems to be a tongue-in-cheek element to this illustration. Or it is possible that two of the above may be equally true...and I'm sure others could come up with other interpretations tooo...