Home › Words › S › sleepsacksleepsacksleepsack means A kind of wearable blanket for a baby.Among words judged in Lexicurio's Arena, sleepsack ranks #28,411 of 42,747 for Qualifying.EtymologyFrom sleep + sack.nounA kind of wearable blanket for a baby.A device resembling a sleeping bag, often fastened with a zipper, that tightly immobilizes the occupant.Definitions & examples from Wiktionary (CC BY-SA 3.0).