1. in or to the next house of在…隔壁
He lives next door to me. 他住在我隔壁。
2. very close to;almost the same as幾乎等于;接近于
Publishing secrets about the country's missiles is next door to treason. 刊登有關國家導彈的秘密等于叛國。
The sick man was next door to death. 這病人即將死亡。