等候 means 'to wait' in a formal, respectful, or patient context — it's more polished and less casual than the simpler 等 (děng). The character 等 means 'to wait' or 'to await', while 候 adds nuance of anticipation, respect, or official procedure; together, they emphasize waiting with attentiveness, often in structured or institutional settings like offices, hospitals, airports, or service counters.

This verb is commonly used when waiting for people (e.g., a superior or guest), appointments, results, or official procedures. It implies patience and formality — you wouldn’t use it for casually waiting for a friend at a café (use 等 instead). 等候 is frequently found in signs ('请等候通知' — 'Please await notification'), announcements, and written instructions. It’s transitive and usually takes an object (e.g., 等候客人, 等候检查), though the object may be omitted if clear from context.