'steady-eyed' originates from English, formed by compounding the adjective 'steady' and the adjectival element 'eyed' (from 'eye'); 'steady' ultimately goes back to Old English 'stǣdig' meaning 'firm, stable', and 'eye' comes from Old English 'eage'.

'steady' changed from Old English 'stǣdig' to Middle English 'stedi/steadi' and eventually became Modern English 'steady'; 'eye' developed from Old English 'eage' into Middle English 'eye', and the compound 'steady-eyed' is a straightforward Modern English formation combining the two elements.

Initially the roots meant 'firm, stable' (for 'steady') and 'eye' (for 'eyed'); the compound originally described someone possessing a steady gaze and has retained that basic meaning into modern usage.