HETEROGENEOUS Nouns, one of the three variations in irregular nouns; or such as are of one gender in the singular number, and of another in the plural. — Heterogeneous, under which are comprehended mixed nouns, are six-fold. 1. Those which are of the masculine gender in the singular number, and neuter in the plural; as, hic tartarus, hæc tartara. 2. Those which are masculine in the singular number, but masculine and neuter in the plural; as, hic locus, hi loci & hæc loca. 3. Such as are feminine in the singular number, but neuter in the plural; as, hæc carbasus, & hæc carbasia. 4. Such nouns as are neuter in the singular number, but masculine in the plural; as, hæc cælum, hi cæli. 5. Such as are neuter in the singular, but neuter and masculine in the plural; as, hæc ræstrum, hi ræstri, & hæc ræstra. And, 6. Such as are neuter in the singular, but feminine in the plural number; as, hæc epulum, hæc epula.