From the point of word formation, the phenomenon of lexical blending is a common productive process, entailing the notion of combination of lexemes in so many languages. In the vast majority of literature on blends, they preserve a linear formation of segments with a shortening of both lexemes. However, in sign languages where morphological categories are mainly encoded by non-concatenative morphology, signed blends can be created by the general mechanism of templatic structures, the combination of lexical bases into a non-linear sequence. Specifically, the main purposes in this study are (i) to provide a comprehensive definition of blending formation in signed modality, (ii) to determine whether there are any structural regularities in the formation of lexical blends in Turkish Sign Language (TID), and (iii) to classify TID blends according to well-defined criteria. The corpus data to be studied currently include 109 blending formations. Overall, the results demonstrate that TID data has familiar properties of blends (named complete blends here) in established spoken languages, as well as modality-specific types of root, simultaneous and initialized blends. We propose a modality-specific categorization, in which blend formation is not limited to linear organization and actual source words.