restrinˈgent noun and adjective

Astringent

restricted area noun

1. One from which the general public is excluded
2. One within which there is a speed limit

restriction endonuclease or restriction enzyme noun

A class of endonucleases with different specificities, often recognizing four or six base pairs and able to cleave DNA at a such a sequence, widely used in genetic manipulation

restriction fragment noun

One of the segments into which a gene has been divided by a restriction enzyme

restrictive covenant noun

A deed that restricts the use of land or property to preserve the value and/or enjoyment of adjoining land or property

restrictive practice noun

1. A trade practice that is against the public interest, such as an agreement to sell only to certain buyers, or to keep up resale prices
2. Used also of certain trade union practices, such as the closed shop, demarcation, working to rule, etc

restrictive temperature noun (biology)

The temperature at which a temperature sensitive mutant organism will not grow (cf permissive temperature)