'limb-related' is a modern English compound formed from 'limb' + 'related'. 'limb' comes from Old English 'lim' meaning 'joint, limb', while 'related' derives from Latin via Old French ('relatus' / 'relater') meaning 'connected' or 'brought back'.

'limb' developed from Old English 'lim' into modern English 'limb', and 'relate' came from Latin 'relatus' through Old French 'relater' to Middle English 'relaten'; the compound 'limb-related' was later formed in modern English by combining these elements to mean 'pertaining to limbs'.

Individually, 'limb' originally meant 'a joint or member of the body' and 'related' meant 'connected'; together the compound has come to specifically mean 'pertaining to or affecting the limbs'.