The Spanish word 'exigibilidad' (meaning 'demandability' or 'the quality of being demandable') has its roots in Latin. It starts with the Latin prefix 'ex-' meaning 'out' combined with 'agere' meaning 'to drive or lead'. These elements formed the Latin verb 'exigere' meaning 'to demand'.

From Latin 'exigere', Spanish developed the verb 'exigir' (to demand). The adjective 'exigible' was then formed by adding the suffix '-ble' (indicating possibility, similar to English '-able'). Finally, the abstract noun 'exigibilidad' was created by adding the suffix '-idad' (similar to English '-ity') to 'exigible', creating a noun that refers to the quality or state of being demandable.

Some related simpler Spanish words include 'exigir' (to demand), which is the basic verb form, and 'exigente' (demanding), which is a common adjective. These words share the same Latin root 'exigere' and maintain the core meaning of demanding or requiring something.

English speakers might recognize the connection to words like 'exact' and 'exigent', which come from the same Latin root 'exigere'. 'Exact' originally meant 'to demand or require' before evolving to mean 'precise or accurate', while 'exigent' means 'requiring immediate attention or demanding' - maintaining a closer connection to the original Latin meaning.