What is a 1st Edition, Thus?
Does the term "THUS" following the description First Edition mean that the edition is not a true first?
The designation "THUS" is a reference that that is the first appearance of a title in that format. Typically the book has appeared previously in a different format. So, you are correct, it's not the true first. Often early books by emerging authors are first released in mass market paper and once they experience their "break through novel" those early books are reprinted in hardback, carrying the THUS designation.
An example would include The Mediterranean Caper by Clive Cussler and The Monkey's Raincoat by Robert Crais.
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