noun Date: 1937 a hand marking seconds on a timepiece mounted concentrically with the other hands and read from the same dial as the minute hand
SWEEP-SECOND HAND
Meaning of SWEEP-SECOND HAND in English
Merriam Webster. Explanatory English dictionary Merriam Webster. Толковый словарь английского языка Мерриам-Уэбстер. 2012