quadrats is a form of:

Quadrat



noun
1.
(1. Printing. A piece of type metal lower than the raised typeface, used for filling spaces and blank lines. Also called quad2. 2. Ecology. Any of a group of small, usually rectangular plots of land arranged for close study of the distribution of plants or animals in an area) កំណល់ដែកសម្រាប់កល់ត្រង់ចន្លោះអក្សរពុម្ព
ENGLISH MEANING
noun
1.
A block of type metal lower than the letters, -- used in spacing and in blank lines.
2.
An old instrument used for taking altitudes; -- called also geometrical square, and line of shadows.