Gun/guns
<p>In the sense of to accelerate an automobile engine, dates from the 1930s, and may have derived from earlier WWI pilots’ jargon, ‘to give it gun’, which meant to accelerate an airplane’s engine. In the sense of an expert, usually in a sporting context, especially cricket, as in a ‘gun cricketer’, ‘gun batsman’, 'gun fielder', 'gun bowler' etc. is originally Australian and NZ colloquial from the late 20th/early 21st century. Guns meaning biceps is American slang, dating from the 1970s, while guns meaning a woman’s breasts, especially if prominent, is also American slang from the early 21st century.</p>