abusage

Partridge in Usage and Abusage would separate the two forms of speech completely:

Usage and Abusage: A Guide to Good English.

Usage and Abusage, by Eric Partridge.

Also, Eric Partridge, in Usage and Abusage, writes that "Irony consists in stating the contrary of what is meant."

On grammar and style in general, Fowler's Dictionary of Modern English Usage is an invaluable guide; a more recent competitor is Eric Partridge's Usage and Abusage.