"zaildar" means: A historical administrative title used in British colonial India for a native officer who supervised a 'zail' — a group of villages, typical.... This is a fairly neutral word with no inherent risk attached. There is no real cause for parental concern; it is descriptive vocabulary rather than something dangerous. If your child uses it, context will usually make the meaning clear. A brief, curious question about where they heard it is generally enough to know whether to follow up.