The verb 'toss' emerged in English during the early 16th century, though its ultimate origin remains obscure. It is likely of Scandinavian origin, possibly related to the Norwegian dialect word 'tossa', meaning 'to strew or spread'. The core semantic logic has consistently involved a quick, light, and often careless motion, whether of the hand throwing an object or of the head or body moving agitatedly. From this literal sense of scattered, jerky movement, the word evolved to describe the act of mixing food lightly, as in a salad, and metaphorically to describe restless mental states, as in 'tossing and turning' at night.

The word 'tossing' is the present participle and gerund form of the verb 'toss'. The root 'toss' is considered a simplex word of uncertain, possibly Middle English, origin. The suffix '-ing' is from Old English '-ende' (present participle) and '-ung' (verbal noun), indicating an ongoing action or state.