as·trin·gent 
(ə-strĭnjənt)
(ə-strĭnjənt)adj.
1. Medicine Tending to draw together or constrict tissues; styptic.
2. Sharp and penetrating; pungent or severe: astringent remarks.
n.
A substance or preparation, such as alum, that draws together or constricts body tissues and is effective in stopping the flow of blood or other secretions.
[Latin astringēns, astringent-, present participle of astringere, to bind fast : ad-, ad- + stringere, to bind; see streig- in the Appendix of Indo-European roots.]
as·tringen·cy n.
as·tringent·ly adv.