I don't think there is, sorry. I only have access to it via the Athens system my university has a subscription with. If a college you went to is a bit sloppy with clearing up their accounts, you might be able to get access through that, and some other institutions have subscriptions but don't widely publicise it - check this list: List of Athens sites that have OED access (http://auth.athensams.net/list_orgs.php).

Otherwise, I guess you're stuck with the usual free online sources like Merriam-Webster and such.