sluice: [14] A sluice is etymologically a device for ‘excluding’ water. The word comes via Old French escluse from Gallo-Roman *exclūsa, a noun use of the feminine past participle of Latin exclūdere ‘shut out’ (source of English exclude [14]). This was a compound verb formed from the prefix ex- ‘out’ and claudere ‘shut’ (source of English close). => close, exclude[sluice etymology, sluice origin, 英语词源]