1702: babysitting Aug 12, 2019
It is not know where '-sit' in 'babysit' comes from, but what is known is that the word evolved in an atypical manner. The first recorded use of the phrase comes from the 1930's in the form of 'babysitter' with 'babysit' following a decade later. This is called backformation, and it may have occurred doubly, as 'babysitting' is documented at least a year before 'babysit' as well, though this could just be due to the means of data-collection, and not so indicative.
Either way, the '-sit' is thought to come from an older meaning of the word, some saying it relates to hens sitting on eggs, and others say it comes from the idea of someone sitting by a crib.
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