In applications for academic jobs that ask for a "copy of transcript", is a "copy of transcript" an unofficial or official copy?
To know for sure, the easiest thing is to email the application contact person for a given job and ask.

My impression is that in many cases, the committee reviewing the transcripts does not really care whether they are official or unofficial, photocopied or not, whatever.  All contain the same information.  If you reach a later stage of the application process, they may require an official transcript to satisfy bureaucratic requirements.

As W88's answer says, every printed version of your transcript is "a copy of your transcript".  "A copy of your transcript" doesn't necessarily mean a photocopy, it just means "a piece of paper with your transcript printed on it".  If you receive a sealed transcript from your school, that is "a copy of your transcript" and you can send it in as-is.