A locked (closed) padlock, as used to secure a latch or chain, or as an icon for a secure internet connection, private account, or locked device. Generally depicted with a gold base and silver shackle. WhatsApp’s design is silver.

Commonly used for content concerning safety, security, privacy, and protection as well as various senses of lock, e.g., locked in/down. As such, it can be used to encapsulate the slang phrase “locked in,” to convey intense focus, commitment, or full mental engagement on a task or goal.