Computing term for a small informational pop-up that appears when hovering over an interface element.
wasei-eigo (Japanese-coined English), from tool hint
See also: ツールチップ
ボタンにマウスを合わせるとツールヒントが表示される。
A tooltip appears when you hover the mouse over the button.
Variant with a middle dot; less common in practice.
Wasei-eigo from English 'tool' and 'hint', likely modeled on 'tooltip'.