'spinelessness' originates from the word 'spineless', which is derived from 'spine' meaning 'backbone' and the suffix '-less' indicating 'without'.

'spineless' evolved from the Old English word 'spinn', meaning 'backbone', and the suffix '-less' was added to denote the absence of a spine.

Initially, it referred to the literal absence of a spine, but over time it evolved to describe a lack of courage or strength of character.