Looking for one word that would describe someone that works so hard that he doesn't sleep. Now, i thought of sleepless and restless but it doesn't fit the description. I was wondering if there was another word besides workaholic.Someone that will be willing to sacrifice sleep to reach their goals.
This is not a single word, but there is the idiom "burning the candle at both ends" that means to work very long hours, including into the night and/or beginning early in the morning. Note that you can either "burn the candle..." or "burn your candle...." There's no difference between using the definite article or the possessive pronoun.
Implicit in this idiom is the idea that it's bad for your physical or mental health. Just like a candle will literally burn out faster if you do suspend it by the middle and light both ends, a person will also figuratively burn out if they burn their candle at both ends for too long. They will likely end up collapsing from mental or physical exhaustion.
It's not a single word, but often someone who is working so hard they don't have time to sleep is said "to be pulling an all-nighter."
"Have you seen Susan in the dorm tonight?"
"No, she has a project due in the morning and is pulling an all-nighter in the library."
Workaholic is usually reserved for someone who works too much, and doesn't necessarily imply a lack of sleep, merely that they're giving up something, be it sleep, social activities, or whatever else.