Other forms: logographs
A logograph is a symbol that represents a whole word. You're probably familiar with logographs like & and $.
Logographs give you no clues about how to pronounce the word associated with them — they just have to be learned and memorized. You can also use this term (or logogram) for other characters or signs that represent a word. Chinese characters and hieroglyphs are often logographs, for example. Logos means "word" in Greek, and graphe means "writing."