[*] 94.
Most nouns of the Fourth Declension are formed from verb-stems, or
roots, by means of the suffix
-tus
(
-sus) (§ 238.
b):
-
cantus,
song, CAN, canō, sing;
cāsus
(for †
cad-tus
), chance, CAD,
cadō
,
fall,
exsulātus,
exile, from exsulō, to be an
exile (
exsul
).
[*] a.
Many are formed either from verb-stems not in use, or by
analogy:
-
cōnsulātus
(as if from
†cōnsulō,
-āre),
senātus
,
incestus
.
[*] b.
The accusative and the dative or ablative of nouns in
-tus (
-sus）
form the Supines of verbs (§ 159.
b): as,
spectātum
,
petītum;
dictū,
vīsū
.
[*] c.
Of many verbal derivatives only the ablative is used as a noun: as,
iussū (
meō
),
by (
my）
command; so
iniussū (
populī
),
without (
the
people's)
order. Of some only the dative is
used: as,
dīvīsuī
.
