Nomophobia is the fear of being out of mobile phone contact.
Is there a name for the fear or phobia of being away from / not being able to reach the internet?
There isn't a word for precisely this fear (yet), but if you want a fancy-sounding neologism, here is fear of away from Internet in transliterated Greek: macriapodiadictuophobia.
If you apply the same technique in Latin, the result would be abinterretemetus.
(In case you're wondering about good ole English, it turns out that it's much more ghastly: awayfrominternetfear.)
However, if you could use words that connote more of an addiction to the internet, then the answers to this question may suffice: cybernaut, nethead, and netizen. Most macriapodiadictuophobes are netheads, and vice versa.
Fear of the internet would be interretephobia, so perhaps fear of being away from it would be abinterretephobia.
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