litmus paper

Anglais

Étymologie

 Composé de litmus et de paper.

Locution nominale

litmus paper

1. Papier tournesol.
   • "ʻOh, we priests pride ourselves on being litmus paper, changing colour in sin's presence,ʼ retorted Father Peregrine, […]." — (Ray Bradbury, The Martian Chronicles, 1950, éd. 2008, ISBN 9780006479239)