lead with (one's) chin
1. Literally, to approach an opponent with one's chin thrust out, thus making it easier to be hit. The cocky fighter led with his chin, daring the underdog to take a swing.
2. By extension, to do or say something aggressively and without caution. The venture capitalist, famous for leading with his chin when it comes to securing investments, is being investigated for fraud and money laundering.
lead with one's chin
Take a risk, behave without caution. For example, Gordon always says exactly what he thinks; he never minds leading with his chin. This term alludes to a boxer leaving his chin, a vulnerable point, unprotected. [Mid-1900s]
lead with your chin
mainly BRITISHIf someone leads with their chin, they behave very aggressively, causing a fight or argument. We don't plan to attack the administration for not spending more on education. There's nothing to be gained from leading with our chins. Note: This expression comes from boxing, and refers to a boxer fighting with their chin sticking out, making it easy for their opponent to hit it.
lead with your chin
behave or speak incautiously. informal This expression originated as mid 20th-century boxing slang, referring to a boxer's stance that leaves his chin unprotected.