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Good night, sleep tight

Julie-Anne Codaire and Anne Murphy
Communications and Marketing
Transport Canada
National Capital Region (NCR)


Most of us have heard the expression good night, sleep tight, don’t let the bedbugs bite, but how many of us have taken the time to ponder the origin of this popular bedtime rhyme? Some historians believe that the expression dates to colonial times. While evidence to support this theory cannot be found, the explanation seems quite plausible.

Before the box spring was invented, people slept on square mattresses or “ticks,” as they called them. Ticks were stuffed with either hay, feathers, grass or even corn shucks and laid on top of ropes fixed across two parallel walls in a weave. These ropes served as a bed frame. In order to have a comfortable sleep, people had to ensure the ropes were secured, of course, and pulled as tight as possible so the tick wouldn’t sag. So, the phrase sleep tight in the expression literally meant “I hope your bed frame stays tight all night so that you can have a good night’s sleep.” As for the second phrase, don’t let the bedbugs bite, some say that elevating the mattress off the floor prevented bugs from reaching the bed and biting their occupant. But then again, if the mattress was made of hay or any other organic product, the bugs might have already made their home there!

Nowadays, some people believe that the rhyme originated from the way in which we put babies to bed. We instinctively try to recreate the warm and comforting environment of the womb by wrapping newborns tightly when putting them to bed. In this case, sleep tight may actually mean to bundle up well so you stay warm and “sleep like a baby.”

According to the Oxford English Dictionary, the word tight in this expression is equivalent to the only surviving use of the adverb tightly meaning “soundly, properly, well, effectively.” As far as theories on this little rhyme go, this explanation is straightforward, but we’re sure you’ll agree that it is the less imaginative and more boring one!