Related Clues:

• That is
• X ___ xylophone
• To be specific
• Words preceding a clarification
• 'Y'know what ___?'
• Cato's clarification
• Relative of exempli gratia
• Abecedary link
• Q ___ queen
• Clarification starter
• In other words
• A ___ apple
• Words of explanation
• Z --- zebra
• Abecedarian phrase