The word "unreachably" refers to something that cannot be reached or accessed. There are several synonyms that can be used in place of this word, depending on the context. For example, the words "inaccessible," "unattainable," and "out of reach" can all be used to convey the idea of something that is impossible to reach. Similarly, the word "impenetrable" can be used to describe something that cannot be accessed due to a physical or metaphorical barrier. Other synonyms include "unreachable," "untouchable," "isolated," and "unapproachable." Each of these words conveys a slightly different nuance, and the choice of which one to use depends on the specific meaning that the author wants to convey.