Super !

Once more unto the crossword….
During our knocking off the morning crossword at coffee time we had a clue that led to the answer “superstitious”. This then engendered the question - if you were only slightly inclined to irrational beliefs and consequential fears would you be stitious? And if something was only slightly unnecessary would it be fluous rather than superfluous?
This led me to realise that the ‘super’ at the start of word is not, as I had unconsciously always thought, simply a prefix to existing words. Once more to the Concise Oxford which demonstrated, as I had by now worked out, that the expression is a prefix but the second part of the word does not always stand alone.