flushtank
noun
Plural: flushtanks
A receptacle filled with water for flushing, especially the tank attached to a toilet bowl.
Examples:
Bruno resolutely prehended the other flushstring as well and pulled gentlishly. A few waterdrops were sputtered from the underrim flushgap and the tankwater refilled in three seconds. He pulled all the way down, and it flushed usually. Water was now replenishing in both flushtanks. The second one, empty, had to be rewatered from the very bottom. The first watertank's level was close to maximum, and the downfading influx got gradually throttled off with a declining hiss. (Context: A boy named Bruno tries to figure out why there are two tanks attached to a single toilet bowl. Source: J∙ Okram - The Mystery of the Rammed Key.)
Translations:
Slovak / Slovenčina (SK): splachovacia nádržka
Czech / Čeština (CZ): splachovací nádržka