An imaginary place inhabited by those who are asleep.(noun)
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Use "slumberland" in a sentence
"What concerns me is whether this message will get to the majority of Malaysians who are still in 'slumberland' and prefer to maintain the status quo."
"If he were to come home at night, I would already be deep in slumberland, quite often with the baby still in my arms."
"But it turns out science has yet to find a magical food that can send us right to slumberland."