I want to refer a hard-working person something far more than referring him a mere "workaholic". What adjective should I choose with "workaholic", if I want to refer him as someone working even harder than a workaholic? What adjective would be proper: "ardent workaholic", "unstoppable workaholic", "hyper workaholic", "super workaholic" or any other adjective with "workaholic"? I agree that "workaholic" is a negative term: used for a person who obsessively work for long hours and thereby neglects other aspects of his life. The context in which I want to use the word "workaholic" is a positive one: I want to heap praise on him. What if I refer him a "relentless taskmaster"? Is there any better alternative? Please suggest.
I'm interpreting "higher degree" to mean that you'd put this particular person ahead (or beyond) a simple workaholic but are trying to describe them only in terms of how much of a workaholic they are. If this last point is true then words like "ardent", "unstoppable", and "hyper" each have an issue because they add additional information. "Super" may work because it doesn't add information beyond a comparison with other (lesser) workaholics.
- Ardent adds an unrequired indication of enthusiasm or passion.
- Unstoppable adds an unrequired indication of inevitability.
- Hyper adds an unrequired indication of energy.
A workaholic may have any, all, or none of those qualities. Some workaholics are dull.
Super workaholic doubles down on the workaholic quality and only the workaholic quality without bringing in other associated, but distict, qualities. It even manages to work in both negitive and positive contexts since it does not indicate aproval or disaproval. It's simply an amplifier.
Alternatives to super: total, serious, extreme
I think the adjective pathological could provide the meaning you seek.
: extreme in a way that is not normal or that shows an illness or mental problem
In US usage, it does not necessarily imply that the person has a actual illness, just that their compulsion is so strong that the effect is similar. This does imply that this is a harmful state of affairs.
A pathological workaholic.
I think the adjective you want is "dedicated" as in "She's dedicated to her job." http://dictionary.reference.com/browse/dedicated. In my opinion this does not have a negative connotation.