照二归精为黄侃所提出之古代汉语音韵学规律。即中古汉语的庄.mw-parser-output .IPA{font-family:"Charis SIL","Doulos SIL","Linux Libertine","Segoe UI","Lucida Sans Unicode","Code2000","Gentium","Gentium Alternative","TITUS Cyberbit Basic","Arial Unicode MS","IPAPANNEW","Chrysanthi Unicode","GentiumAlt","Bitstream Vera","Bitstream Cyberbit","Hiragino Kaku Gothic Pro","Lucida Grande",sans-serif;text-decoration:none!important}.mw-parser-output .IPA a:link,.mw-parser-output .IPA a:visited{text-decoration:none!important}、初、崇、生四声母，上古归于精、清、从、心四声母。黄侃《黄侃论学杂着》中的《声韵略说》：“由精而变者，曰庄；由清而变者，曰初；由从而变者，曰床；由心而变者，曰邪，曰疏。”杨柳桥《汉语音韵学讲义》认为，清人夏燮己于《述韵》初步提出“照二归精”的看法，到黄侃提出更完整的说法。