1. Depressed like a navel

See also: concave

• Yemeni rial
• yen
• Yenisei
• Yenisei River
• Yenisei-Samoyed
• Yeniseian
• Yenisey
• Yenisey River
• yenta
• yeoman
• yeoman of the guard
• yeomanry
• yep
• yer
• yerba buena
• yerba mansa
• yerba santa
• Yerevan
• Yerkes
• Yersin
• Yersinia pestis
• Yerupaja
• Yerwa-Maiduguri
• yes
• yes-man