1.2. Non-core lexicon
To the non-core lexicon belong signs which can be defined as being visually-motivated, in that they exploit the spatial properties of the three-dimensional space for the realisation of concepts. Therefore, they display a higher degree of iconicity despite being fully linguistic, and not gestural, elements. Considering that they usually convey many information simultaneously, they tend to be polymorphemic rather than monomorphemic constructions. Differently from core lexicon signs, which display a fixed form, non-core lexicon signs can be modified in their articulation in order to convey different meanings. The signs typically defining the non-core lexicon are classifier constructions, pointing signs, buoys and other signs whose origin is the result of visual metaphors such as metonymy and synecdoche (poetic devices using words not in their literal meaning but to refer to some other abstract concepts, discussed in PRAGMATICS 9). Being visually motivated, non-core lexicon signs exploit the signing space in an isomorphic and non-categorical manner in order to convey spatial descriptions.
Non-core lexicon in LIS is largely built on visual metaphors, in which iconic mapping focuses on semantic features that the source and the target domains share. Specifically, iconic features of sign language metaphors are the expressive manifestation of the blending process that occurs in the minds of the signer and the target. This kind of metaphors can occur both in formal and poetic registers, with a majority of occurrences in poetry. Being metaphors, in order to be understood interlocutors must have a comprehensive cultural knowledge of Deafness and Deaf culture. In LIS metaphors, vision plays a crucial role in that it is conceptualized as a complex tool for elaborating and transforming knowledge, and it is often found in metaphors related to mind and cognition. In general, LIS metaphors are grounded on visual and tactile experiences familiar to deaf people (see PRAGMATICS 9 for further details).
