litmus definition by Webster's New World
Origin: Old Norse litmose, lichen used in dyeing ; from litr, color (akin to Gothic wlits, face ; from Indo-European an unverified form wtu-, appearance ; from base an unverified form wel-, to see from source Classical Latin voltus, expression, Welsh gweled, to see) plush mosi, moss
litmus definition by American Heritage Dictionary
Origin: Middle English litemose (of Scandinavian origin; akin to Old Norse litmosi, dyer's herbs litr, color, dye + mosi, bog, moss) and Middle English lykemose (from Middle Dutch lijkmoes, variant of lēcmoes : lēken, to drip + moes, moss).
litmus - Cultural Definition
In chemistry, a kind of paper used to tell whether a solution is an acid or a base. Acids turn blue litmus paper red; bases turn red litmus paper blue. Other testing paper or sophisticated instruments can be used to measure the pH of a solution more precisely.
- The term litmus is often used to refer to a general and simple test: “Your vote on this issue is a litmus test of your political philosophy.”
litmus - Medical Definition
litmus - Science Definition