- ill-fated
- ill-favored
- ill feeling
- ill-fitting
- ill-founded
- ill-gotten
- ill health
- ill-housed
- ill humor
- ill-humored
- illiberal
- illicit
- Illimani
- illimitable
- illimitables
- Illinoian
- Illinois
- Illinois
- Illinois Benedictine College
- Illinois bundleflower
- Illinois Central College
- Illinois College
- Illinois Eastern Community College-Frontier
- Illinois Eastern Community College-Lincoln Trail
- Illinois Eastern Community College-Olney Central