IPA: //ˈmiːləs//
KK: /ˈmēləs/
Not having a meal or meals; lacking food.
After a long day of work, I felt mealless and tired.
Mealless is formed from "meal" (from Old English *mæl*, meaning a portion or a meal) and "-less" (meaning without). The word "mealless" means without a meal or lacking a meal.
Think of 'meal' as a portion of food and '-less' meaning without — so mealless describes a state of being without food.