Go commando
Definition 1 of 1
Pro Tip 1/3Casual Speech
The phrase is casual and might not be appropriate in formal or professional settings. 
At the beach, some men prefer to go commando under their shorts.
Pro Tip 2/3Cultural Awareness
Be aware some cultures may find discussing personal clothing habits like 'going commando' impolite or embarrassing. 
When she moved abroad, she learned that 'going commando' was a more sensitive topic there.
Pro Tip 3/3Humorous Tone
The phrase often carries a humorous connotation and can amuse or provoke laughter in casual conversations. 
The party was so spontaneous, he showed up in a rush and went commando.