'musicalness' originates from English, specifically the word 'musical' combined with the suffix '-ness', where 'musical' comes (via Old French and Late Latin) from Latin 'musicalis' and ultimately from Greek 'mousikē' (related to the Muses) meaning 'of the arts of the Muses'.

'musical' developed from Late Latin 'musicalis' (from Latin 'musica') and Old French 'musical', while the suffix '-ness' is from Old English '-nes(s)e'; these elements combined in Modern English to form 'musicalness'.

Initially associated with things pertaining to the Muses or to music itself, the word evolved to denote the property or state of being musical — i.e., possessing musical quality or ability.