extent (n.)youdaoicibaDictYouDict[extent 词源字典]
early 14c., from Anglo-French extente, estente "extent, extension;" in law, "valuation of land, stretch of land," from fem. past participle of Old French extendre "extend," from Latin extendere "to spread out, spread" (see extend). Meaning "degree to which something extends" is from 1590s.[extent etymology, extent origin, 英语词源]