掩码

掩码	yǎn mǎ	(computing) mask
掩	yǎn	to cover up; to conceal / to close (a door, book etc) / (coll.) to get (one's fingers etc) caught when closing a door or lid / (literary) to launch a surprise attack
码	mǎ	(archaic) agate / (bound form) standard weight used with a balance scale / number / (computing) code / (clothing) size / yard (unit of length) / (coll.) kilometers per hour (informal misuse of "yard" to mean kph in speed references) / (coll.) to pile up; to stack / classifier for matters, items, situations etc (esp. when indicating whether they are the same or different, as in 不是一码事 "not the same thing") / (Tw, HK) (finance) unit of 25 basis points (i.e. a 0.25% change in interest rate)