Lexigram

Near-synonyms: lexigraph (polysemic, sometimes synonymous), logogram, logograph

Instead of ASL, Savage-Rumbaugh used an extensive ‘lexigram’, a matrix of 256 geometrical shapes on a board. Instructors touch the symbols, which represent verbs and nouns, to create simple requests or commands.

Each chimp next learned to press the lexigram corresponding to a food item that it had seen the teacher put in an opaque container.