Our study focuses on the perception of the iconicity of handshapes – one of the formational parameters of the sign in signed language. Seventy Hebrew speakers were asked to match handshapes to Hebrew translations of 45 signs, which are specified for one of the handshapes in Israeli Sign Language. The results show that participants reliably match handshapes to corresponding sign translations for highly iconic signs, but are less accurate for less iconic signs. This demonstrates that there is a notable degree (...) of iconicity in the lexicon of ISL, which is recognizable even to non-signers. The ability of non-signers to detect handshape to form is explained by the fact that word meanings are understood by both deaf and hearing peoples via the mental elaboration of simple iconic sources in which handshape meanings are grounded. The results suggest that while language external iconic mapping could ease the learning of direct iconic forms, it has a more limited capacity to help hearing non-signers learn indirect and opaque forms. The full semiotic distribution of handshapes in the lexicon and their use in language remain difficult for hearing non-signers to understand and depends on more specific language and cultural knowledge. (shrink)