I am writing a report and need to describe a word in terms of its letters (not one particular word, the concept of a word in general). I considered writing that a word is a string of letters, but wasn't sure if this was bad english in a non-coding context. If it is bad english, are there any other ways I could use to do this?
The phrase a string of letters is not restricted to coding contexts. It is a common phrase in linguistics, among other things as one of the definitions of word. Here are a few examples:
A word is a string of letters with no spaces that has a meaning and can be used in a sentence. (Why the 'millionth word' story is silly )
The question isn’t whether or not irregardless is a word, because that’s such an ill-defined question. Of course it’s a word, as it’s a string of letters with a fairly well-agreed-upon intended meaning, a string that is standardly separated from other words in a sentence by spaces. ('Irregardless' has a posse)
The phenomenon whereby a spam filter blocks a word or phrase because of a string of letters that constitutes an obscene word is called the Scunthorpe problem, so called because residents of the English town of Scunthorpe could not set up email accounts with AOL in the 1990s because of a four-letter word hidden within the name. (The Scunthorpe Problem)