In an Australian PhD dissertation, the Oxford English Dictionary would be the obvious choice when needing to make reference to a dictionary definition.

However, I am writing for an audience of (mostly) American computer scientists and would like to follow US conventions.

**Which dictionary would be widely regarded as the source of the most authoritative, prestigious and "academic" definitions within the US?**


(There is a related question at http://english.stackexchange.com/questions/12480/us-equivalent-to-the-oxford-english-dictionary but the question and answers are based on a reader's point of view, rather than as an authoritative source)