丸椅子 is read as まるいす (maruisu) and means stool.
まるいす
maruisu
まるめんこ
round menko
まるこぶね
wooden transport ship used on Lake Biwa
ほじょいす
auxiliary seat
たたみいす
folding (collapsible) chair
いす
chair
くるまいす
wheelchair
さんきゃくいす
three-legged stool
でんどうくるまいす
electric wheelchair
かいてんいす
swivel chair
でんきいす
electric chair
くうきいす
chain of people sitting on each other's laps
ゆりいす
rocking chair