From Middle English steire, staire, stayre, stayer, steir, steyre, steyer, from Old English stǣġer (“stair, staircase”), from Proto-West Germanic *staigri, from Proto-Germanic *staigriz (“stairs, scaffolding”), from Proto-Indo-European *steygʰ- (“to walk, proceed, march, climb”). Cognate with Dutch steiger (“a stair, step, wharf, pier, scaffolding”), Middle Low German steiger, steir (“scaffolding”), German Low German Steiger (“a scaffold; trestle”). Related to Old English āstǣġan (“to ascend, go up, embark”), Old English stīġan (“to go, move, reach; ascend, mount, go up, spring up, rise; scale”), German Stiege (“a flight of stairs”). More at sty.