度假 (dù jià) means 'to go on vacation' — it specifically refers to taking a leisure trip away from home. This contrasts with 休假 (xiū jià), which is a broader term for taking any kind of leave (including staying home), and 放假 (fàng jià), which means having a scheduled holiday (like school or public holidays). 请假 is 'to ask for leave' and 出差 is 'to go on a business trip'.