| Y2L | Yangyang Underground Laboratory 
| Others |
| Y2M | You're too Much
| Others |
| Y3 | Year 3000
| Others |
| Y3 | Yeoman Third Class
| Others |
| Y31 | West Branch Community Airport, West Branch, Michigan USA
| Others |
| Y3A | Building housing the Faculty of Arts at Macquarie University (not an acronym)
| Others |
| Y3A | Year Three Adaptability
| Others |
| Y3W | Your Three Words
| Others |
| Y47 | Oakland Southwest Airport, New Hudson, Michigan USA
| Others |
| Y58 | Sleepy Eye Municipal Airport, Sleepy Eye, Minnesota USA
| Others |
| Y8 | Y8 is short for yeet, which is expressing excitement.
| Others |
| Y83 | Sandusky City Airport, Sandusky, Michigan USA
| Others |
| Y87 | Empire Airport, Empire, Michigan USA
| Others |
| Y93 | Atlanta Municipal Airport, Atlanta, Michigan USA
| Others |
| Y95 | Hillman Airport, Hillman, Michigan USA
| Others |
| Y96 | Onaway Airport, Onaway, Michigan USA
| Others |
| YA | A Yelling Allowed
| Others |
| YA | Yalcin Adal
| Others |
| YA | Yanmar America
| Others |
| YA | Yassir Arafat
| Others |
| YA | Year Ago
| Others |
| YA | Years Ago
| Others |
| YA | Yellowstone Alliance
| Others |
| YA | Yet Another
| Others |
| YA | Yorkshire Apples
| Others |
| YA | Yosemite Antiques
| Others |
| YA | You Are
| Others |
| YA | Young Adolescent
| Others |
| YA | Young Adult
| Others |
| YA | Young Adults
| Others |
| YA | Young America
| Others |
| YA | Young Americans
| Others |
| YA | Young Arrest
| Others |
| YA | Young Artists
| Others |
| YA | Young Audiences
| Others |
| YA | Your A**
| Others |
| YA | Your Account
| Others |
| YA | Youssef Amin
| Others |
| YA | Youth Activism
| Others |
| YA | Youth Advocacy
| Others |
| YA | Youth Arm
| Others |
| YA | Youth Association
| Others |
| YA | Youth Authority
| Others |
| YA | Yuffie Aogiri
| Others |
| YAA | Akosa Antwi
| Others |
| YAA | Anahim Lake, British Columbia, Canada
| Others |
| YAA | Yale Alumni Association
| Others |
| YAA | Yellowstone Alliance Adventures
| Others |
| YAA | Yet Another Acronym
| Others |
| YAA | York Adult Assessment
| Others |