a. Feminine: carō, _flesh_.

2. Nouns in -or.

a. Feminine: arbor, _tree_.

b. Neuter: aequor, _sea_; cor, _heart_; marmor, _marble_.

3. Nouns in -ōs.

a. Feminine: dōs, _dowry_.

b. Neuter: ōs (ōris), _mouth_.

4. Nouns in -er.

a. Feminine: linter, _skiff_.

b. Neuter: cadāver, _corpse_; iter, _way_; tūber, _tumor_; ūber, _udder_.
Also botanical names in -er; as, acer, _maple_.

5. Nouns in -ĕs.

a. Feminine: seges, _crop_.

45. Exceptions to the Rule for Feminines.

1. Nouns in -ās.