crowded \crowded\ adj. 1. overfilled or compacted or concentrated; filled to excess; as, a crowded program. Opposite of {uncrowded}. Note: [Narrower terms: {full, jammed, jam-packed, packed}] [WordNet 1.5] 2. filled with a crowd; as, a crowded marketplace. [PJC] 3. having an uncomfortable density of people; filled to excess with people; as, crowded trains; a crowded theater. [PJC]