'bareknuckled' originates from English, specifically a compound of 'bare' and 'knuckle', where 'bare' meant 'without covering' and 'knuckle' referred to the fist.

'bareknuckled' changed from the compound phrase 'bare knuckle' and from the noun phrase 'bare-knuckle' (as in 'bare-knuckle boxing') and eventually became the adjective 'bareknuckled' used to describe both literal and figurative uncompromising fighting.

Initially, it meant 'without gloves' referring to physical fighting, but over time it also evolved to mean 'uncompromising' or 'ruthless' in nonliteral contexts.