The Spanish word 'inimputable' comes from adding the negative prefix 'in-' to the word 'imputable', which itself derives from the verb 'imputar'. Going further back, 'imputar' comes from Latin 'imputare' meaning 'to attribute or charge to', which was formed by combining the Latin prefix 'in-' (meaning 'in, into') with 'putare' (meaning 'to think or consider'). The modern Spanish word 'inimputable' thus literally means 'that which cannot be imputed or attributed to someone'.

This is a good example of how prefixes can stack up in Spanish - here we see both the original Latin 'in-' that helped form 'imputar', plus a second Spanish 'in-' prefix added later to create the negative form 'inimputable'.

Some simpler related Spanish words include 'imputar' (to impute or attribute), 'imputable' (that which can be imputed), and 'imputación' (imputation, accusation). All these words share the core meaning of attributing or assigning responsibility for something.

English speakers might recognize the connection to words like 'impute', 'imputable', and 'computation'. These all trace back to Latin 'putare' (to think or consider). While 'impute' maintained the sense of attributing or assigning something to someone, 'compute' (which comes from Latin 'computare', another compound of 'putare') developed more specifically to mean calculating or reckoning - both activities that involve careful consideration.