Generally speaking, using the term "Large oriental rug" won't provide the best search results. A Large is unofficially accepted as a carpet which is approximately 9'x12' or 10'x14'. However, the word "Rug" is often in reference to a piece which measures approximately 5'x8' or smaller (sometimes 6'x9' or smaller.)
Many people use the words Rug and Carpet interchangeably, which is not necessarily a bad thing, just more semantics than anything else. However, if you are searching for a "large rug" you may want to consider the following as well.
A Mansion Size Carpet: This often refers to Oriental Carpets measuring a minimum of 10' wide, and a maximum of 12' wide (give or take.) Length is a minimum of 15' long, and a maximum of 20' long.
A Palace Size Carpet: This often refers to everything over the size of a mansion carpet. A Palace Carpet has the connotation of a certain customized size which is unusually large: standard looms for larger rugs rarely exceed 12' width. So, for this instance, a Palace Size Carpet would be a carpet which exceeds 12' width, and exceeds 20' in length.
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