any of various materials depending on the sense of sight, as films, slides, photographs, etc., used as aids in teaching.
Origin of visual aid
First recorded in 1910–15
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
devices, such as films, slides, models, and blackboards, that display in visual form material to be understood or remembered
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012