predeterminer , determiner , & pronoun
- used to refer to two people or things, regarded and identified together: [as predeterminer]:both his parents indulged him [as determiner]:I urge you to read both these books she held on with both hands he was blind in both eyes [as pronoun]:a picture of both of us together Jackie and I are both self-employed he looked at them both
Middle English: from Old Norse báthir
When both is used in constructions with and, the structures following ‘both’ and ‘and’ should be symmetrical in well-formed English. Thus, studies of zebra finches, both in the wild and in captivity is stronger and clearer than studies of zebra finches, both in the wild and captivity. In the second example, the symmetry or parallelism of ‘in the wild’ and ‘in captivity’ has been lost.