लुक् [ luk ] [ luk ]2 ( prob. fr. √ [ luñc ] ) , and gram. term to express " the dropping out " or , " disappearance " of Pratyayas or affixes ( the symbols [ luk ] , [ lup ] , and [ ślu ] are distinguished from [ lopa ] , q.v. , and are called [ lumat ] , as containing the syllable [ lu ] ) .