'nonallocability' is formed in English by prefixing 'non-' (meaning 'not') to 'allocability', where 'allocability' comes from 'allocate' + '-ability'.

'allocate' originates from Latin 'allocare' (from ad- 'to, toward' + locare 'to place'), which entered English via Late Latin and French; 'allocate' produced the noun 'allocability' (the capacity to be allocated), and modern English formed 'nonallocability' by adding the negative prefix 'non-'.

Initially, the root sense concerned 'placing' or 'assigning' (from Latin 'locare' 'to place'); over time it evolved into the modern technical sense of whether something can be assigned or apportioned, and 'nonallocability' specifically denotes the absence of that capacity.