Wikipedia
A Weyr is a collection of dragons, their riders and support staff in Anne McCaffrey's fictional world of Pern.
The function of a Weyr is to fight Thread, a spore that originates in the Oort cloud of the Rukbat solar system, carried by a planetoid referred to as the Red Star with a loose elliptical orbit. The time during which Thread falls is called a Pass. These Passes last about 50 years, usually with a break of 200 years between, although extended periods have been known to occur due to orbital mechanics.
Usage examples of "weyr".
Holds out of solid rock and becoming so busy with their pursuits, that they did not realize that there were only a few dragons in the skies, and only one Weyr of dragonriders left on Pern.
Name-Song for the current wingleaders of Benden Weyr so her Sea Hold would know their dragonmen.
And the women of the Weyr came every spring and fall to berry or cut withies and grasses.
But by the time troops marched on the Weyr, the situation had drastically changed.
You have my permission to leave the Weyr and take up residence where you will.
Lords of Pern into disbanding their army when they were all set to coerce the Weyr and dragonmen?
Where had she gone to today when, for the first time in weeks, he had been able to get all the wings out of the Weyr just so he could teach her to fly between?
They had entered the well-lighted weyr, so he did not miss the trenchant look she shot him over her shoulder.
Like others who survived Impression, Kylara had found certain aspects of Weyr life exactly suited to her temperament.
When Weyr business or dragonlore were discussed, she suspended the antipathy he knew she felt for him.
They glided down the Weyr Bowl, over the misty bathing lake, toward the feeding ground at the opposite end of the long oval that comprised the floor of Benden Weyr.
The striated, precipitous walls were pierced with the black mouths of single weyr entrances, deserted at this time of day by the few dragons who might otherwise doze on their ledges in the wintry sun.
Flying as far away as Benden Hold itself, nestled against the foothills above Benden Valley, the Weyr Peak a far point against the noonday sky, Lessa did not neglect to visualize a clearly detailed impression each time.
And then they were above the quiet, peaceful wintry Weyr as if they had never paradoxically visited Ruatha.
Lessa was shuddering, her eyes frantically taking in the reassuring sight of the Weyr Bowl, hoping she had not somehow shifted backward in time yet again.