汗牛冲栋是什么意思

汗牛充栋
hànniú-chōngdòng
[enough books to make the ox carrying them sweat or to fill a house to the rafters—an immense number of books] 形容书籍存放很多。用牛运输,牛累得出汗;书堆满屋子,顶到栋梁
又有徒党传习,日不 暇给,又其书汗牛充栋。——宋·陆九渊《与林叔虎书

看的书很多，可以说汗牛充栋