包涵 is a polite, self-deprecating word you use to ask someone to be tolerant or forgiving of your mistakes, shortcomings, or lack of refinement — it's a fixed expression in the phrase '请多包涵' (please be lenient with me). It can also mean 'to contain' in a formal, literary sense ('his speech contained profound insights'). Unlike 原谅 or 抱歉, 包涵 places the burden on the listener's magnanimity rather than the speaker's apology.