1) One who has no idea which words to use correctly in a sentence.

2) Someone who has never used and has no intention of using a dictionary.... EVER.

3) One who has no idea what Merriam Webster's dictionary is.

4) A serious lack of knowledge of the English language.
Dave is completely diction deficiant... He is excellent at creating run on sentences though.
by TheCradle August 31, 2007
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