Currently there seems to be no clear defintion of these terms. It would be beneficial to have one to

• communicate to users what they means
• give a guideline to custome Publisher, Reporter, BuildStep authors how to set these results
• give a common vocabulary to developers and users

I'd propose to put these defintions into an easily accessible page - i.e. in the Jenkins UI itself.

See https://groups.google.com/forum/?hl=de#!topic/jenkinsci-dev/2rMdYX3WMwo for the related discussion on the developers mailing list