A coloring material (obtained from lichens) that turns red in acid solutions and blue in alkaline solutions; used as a very rough acid-base indicator.

synonym: litmus.

Roget 463: experiment; essay etc. (attempt) 675; analysis etc. (investigation) 461; screen; trial, tentative method, t=atonnement.    verification, probation, experimentum crucis [Lat.], proof, (demonstration) 478; criterion, diagnostic, test, probe, crucial test, acid test, litmus test.    crucible, reagent, check, touchstone, pix^†; assay, ordeal; ring; litmus paper, curcuma paper^†, turmeric paper; test tube; analytical instruments etc. 633.    empiricism, rule of thumb.    feeler; trial balloon, pilot balloon, messenger balloon; pilot engine; scout; straw to show the wind.    speculation, random shot, leap in the dark.    analyzer, analyst, assayist^†; adventurer; experimenter, experimentist^†, experimentalist; scientist, engineer, technician.    subject, experimentee^†, guinea pig, experimental animal.    [experimental method] protocol, experimental method, blind experiment, double-blind experiment, controlled experiment.    poll, survey, opinion poll.    epidemiological survey [Med.], retrospective analysis, retrospective survey, prospective survey, prospective analysis; statistical analysis.    literature search, library research.    tryout, audition.    [results of experiment] discovery etc. 480; measurement etc. 466; evidence etc. 467.    [reasoning about an experiment] deduction, induction, abduction.    ... show more

Dutch: lakmoes
Polish: lakmus

A test that relies on a single indicator.