'unconditionalness' originates from English, specifically formed from the prefix 'un-' + the adjective 'conditional' + the suffix '-ness', where 'un-' meant 'not', 'conditional' comes via Old French and Medieval Latin from Latin 'conditio' (meaning 'agreement, stipulation'), and '-ness' is a noun-forming suffix indicating a state or quality.

'unconditionalness' developed in Modern English by adding the suffix '-ness' to 'unconditional'. 'Conditional' came into English via Old French 'condicion' and Medieval Latin 'conditio', and eventually became the modern English 'conditional' through Middle English.

Initially, the root 'condition' referred to an 'agreement' or 'stipulation'; over time 'conditional' came to mean 'depending on conditions', and 'unconditionalness' later came to mean 'the state of having no conditions' or 'complete absence of qualifications'.