Dictionary > Litmus


(Science: chemistry) a dyestuff extracted from certain lichens (Roccella tinctoria, Lecanora tartarea, etc), as a blue amorphous mass which consists of a compound of the alkaline carbonates with certain colouring matters related to orcin and orcein.
litmus is used as a dye, and being turned red by acids and restored to its blue colour by alkalies, is a common indicator or test for acidity and alkalinity.
(Science: chemistry) litmus paper, unsized paper saturated with blue or red litmus, used in testing for acids or alkalies.
Origin: D. Lakmoes; lak lacker – moes a thick preparation of fruit, pap, prob. Akin to E. Meat: cf. G. Lackmus. See lac a resinous substance.

You will also like...

Community Patterns

Learn about community patterns and the ecological factors influencing these patterns. Revisit some of the ecosystems you..

Homeostatic Mechanisms and Cellular Communication
Homeostatic Mechanisms and Cellular Communication

Homeostasis is the relatively stable conditions of the internal environment that result from compensatory regulatory res..

kinesin motor proteins transporting molecules across microtubules
Movement of Molecules Across Cell Membranes

Molecules move within the cell or from one cell to another through different strategies. Transport may be in the form of..


Humans are diploid creatures. This means that for every chromosome in the body, there is another one to match it. Howeve..

An artistic depiction of a human embryo
Growth and Development of a Human Baby

Upon fertilization, a zygote forms and develops into an embryo. This tutorial elaborates on the growth and development f..

Principles of Hormonal Control Systems
Principles of Hormonal Control Systems

Hormones are essential in the regulation of the activity of the various biological systems of the human body. The ineffi..