It's not my definition, that's how the CAN-SPAM Act of 2003 (applicable to US only) defines spam and most marketers are familiar with since it's been around for 15 years. Of course the laws are different in Europe and Canada.
One of the factors I didn't mention in previous comment is presence of physical mail address.
Not sure what "unfortunately for me" is in reference to - BigMailer isn't a platform for cold emails (there are plenty others that specialize in cold email campaigns) and Amazon SES doesn't give a free pass on the practice either.