If you have any context for where you encountered this word, it might be possible to figure out what it was supposed to be. For example:
* Could it be a typo for another word? Maybe it was meant to be "squash," "squish," or something else entirely.
* Is it a slang term or a joke? If you heard it in a specific group or situation, it might be an inside joke or a regional term.
Without more information, it's impossible to determine the meaning of "squadush."