For various Universities it means, Pass Second Year Optional.
In the context of Rajasthan University results, "PSYO" likely stands for "Psychology." It's common for universities to use abbreviations or codes for different subjects or courses in their result sheets or transcripts. In this case, "PSYO" is likely the abbreviation used to represent Psychology as a subject or course. If you're unsure about any specific abbreviation in your results, it's best to consult with the university's administration or academic advisors for clarification.
Pass in Present Subject Only