A shtukh is a insult, often clever but always devastating. The following is from the INTRODUCTION to an important book on halakhah, the Simlah Hadashah and Bekhor Shor. This book is a classic work on the laws of slaughtering. To introduce this book, the author writes the following:
The book P'ri Hadash on Yoreh De'ah came into my possession and I looked at it carefully, with God's help. While it looks from the book that the author was a great Torah scholar, sharp and asking [good questions], nevertheless it seems that he did not write [pun: bind] it with a careful thread. He reaches conclusions as he explained in his introduction, that he only spent two years [writing it]. Therefore, in most places he disagrees with our later teachers and sometimes even on the early ones. He is lenient contrary to them and contrary to the law. One who looks in the book will choose his words, because we find that in all places he permits too much. Therefore, I say that Hizkiyah, the great rabbi mentioned, should not fool you into being lenient against our famous rabbis because you will find in this book, with God's help, a response to most of his disputes on the words of the decisors. From these you can judge on the rest...I learned part of the laws of slaughtering with a fellow who wanted to be a shohet and therefore memorized the Simlah Hadashah. However, after learning through the laws carefully with him, I found that the P'ri Megadim often defended the P'ri Hadash and made extremely solid arguments against the Simlah Hadashah/Bekhor Shor. It seems to me that the P'ri Megadim frequently proves the P'ri Hadash to be correct over the Bekhor Shor.