[ lahy-sis ]
/ ˈlaɪ sɪs /
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noun, plural ly·ses [lahy-seez]. /ˈlaɪ siz/.
Immunology, Biochemistry. the dissolution or destruction of cells by lysins.
Medicine/Medical. the gradual recession of a disease.Compare crisis (def. 4).
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Origin of lysis

1815–25; <New Latin <Greek lýsis a loosening, releasing, equivalent to ly-, variant stem of lȳ́(ein) to loosen, release + -sis-sis

Other definitions for lysis (2 of 2)


a combining form with the meaning “breaking down, loosening, decomposition,” used in the formation of compound words: analysis; electrolysis; paralysis.

Origin of -lysis

From Greek; see origin at lysis
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How to use lysis in a sentence

British Dictionary definitions for lysis (1 of 2)

/ (ˈlaɪsɪs) /

noun plural -ses (-siːz)
the destruction or dissolution of cells by the action of a particular lysin
med the gradual reduction in severity of the symptoms of a disease

Word Origin for lysis

C19: New Latin, from Greek, from luein to release

British Dictionary definitions for lysis (2 of 2)


n combining form
indicating a loosening, decomposition, or breaking downelectrolysis; paralysis

Word Origin for -lysis

from Greek, from lusis a loosening; see lysis
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Medical definitions for lysis (1 of 2)

[ līsĭs ]

n. pl. ly•ses (-sēz)
The gradual subsiding of the symptoms of an acute disease; a form of the recovery process.
The dissolution or destruction of cells, such as blood cells or bacteria, as by the action of a specific lysin.

Medical definitions for lysis (2 of 2)


Decomposition; dissolving; disintegration:hydrolysis.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

Scientific definitions for lysis

[ līsĭs ]

The disintegration of a cell resulting from destruction of its membrane by a chemical substance, especially an antibody or enzyme.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.