fās, n., _right_. nefās, n., _impiety_.
Ä«nstar, n., _likeness_. nihil, n., _nothing_.
māne, n., _morning_. secus, n., _sex_.

1. With the exception of māne (which may serve also as Ablative, _in the
morning_), the nouns in this list are simply Neuters confined in use to the
Nominative and Accusative Singular.

Heteroclites.

59. These are nouns whose forms are partly of one declension, and partly of
another. Thus:--

1. Several nouns have the entire Singular of one declension, while the
Plural is of another; as,--

vās, vāsis (_vessel_); Plu., vāsa, vāsorōum, vāsīs, etc.
jūgerum, jūgerī (_acre_); Plu., jūgera, jūgerum, jūgeribus, etc.

2. Several nouns, while belonging in the main to one declension, have
certain special forms belonging to another. Thus:--

a) Many nouns of the First Declension ending in -ia take also a Nom. and
Acc. of the Fifth; as, māteriēs, māteriem, _material_, as well as
māteria, māteriam.

b) Famēs, _hunger_, regularly of the Third Declension, has the Abl. famē
of the Fifth.