411 REFERENCE · Wiktionary
Sloan letter
Reference material by Wiktionary contributors. This retains its source identity and is not 411 news reporting.
English
+s
Etymology
They were designed by Louise Sloan in 1959.
Noun
Any of a set of standard optotypes resembling the letters C, D, H, K, N, O, R, S, V and Z.
en eponyms