Ablative with Special Deponent Verbs

Five important deponent verbs regularly govern an ablative complement: ūtor “use,” fruor “enjoy,” fungor “perform,” potior “gain possession of,” and vēscor “feed on.” English translates all five with active verbs and usually follows them with direct objects, so English speakers are strongly tempted to use the accusative. Latin instead presents the associated thing in the ablative, an inherited instrumental pattern that has become part of each verb’s valency.

The five verbs

These verbs are deponent: their finite forms look passive but normally have active meaning. Their special complement is a separate fact—you cannot assume that every deponent takes the ablative.

Ūtor: using a thing or resource

Ūtor takes the thing employed in the ablative. That complement may be a physical instrument, a plan, a right, someone’s help, or an opportunity.

The perfect ūsī sumus is morphologically passive-looking but semantically active: “we used,” not “we were used.” Its ablative cōnsiliō is retained across tense and non-finite forms because the verb’s valency has not changed.

English “use” makes cultrum or “the knife” a direct object. That English syntax is irrelevant to Latin. Historically, the construction can be understood as “employ oneself by means of the knife,” but in Classical Latin the instrumental relation has lexicalized: speakers simply learned ūtor with the ablative.

The common compound abūtor “misuse, abuse; use up” also governs the ablative in Classical prose: patientiā nostrā abūtitur “he abuses our patience.” Other rare compounds belong mainly to (archaic) or specialized usage and should be recognized from a dictionary rather than imitated.

Fruor: enjoying a good

Fruor takes in the ablative the good, condition, or relationship from which someone derives enjoyment or benefit. Compared with ūtor, it focuses on enjoying the good itself, not employing it as a means.

Roman philosophical prose sometimes sharpens the contrast between “using” something as a means and “enjoying” it as an end. Ordinary language does not turn that philosophical distinction into a rigid rule for every context, but the basic lexical contrast is useful.

Compounds such as perfruor “enjoy fully” and the uncommon dēfruor retain the ablative. Perfruor is especially at home in (formal) or (literary) prose.

Fungor: discharging a duty

Fungor combines most naturally with nouns of duty, office, task, or service—especially mūnere and officiō. It means performing what a role requires, not merely “doing” any random object.

The participle fūnctus has active meaning: the envoy performed the mission. The compound dēfungor can mean “finish, discharge” and, with life or an absolute use, “die”; it preserves ablative government when a complement is expressed. These uses are mostly (formal), administrative, or (literary).

Potior: obtaining possession—and its genitive

Potior normally takes the ablative of the thing seized, acquired, or controlled.

Unlike the other four verbs, potior has a genuine Classical alternative: it can take the genitive, and rērum potīrī “gain control of affairs, become supreme” is an established expression.

There is no responsible way to erase this variation. For production, use the well-established ablative with ordinary objects such as castrīs, imperiō, and victōriā, but learn the genitive rērum expression as a genuine lexical pattern. Both constructions occur in (formal) prose and (literary) narrative.

Vēscor: feeding on something

Vēscor takes the food or diet in the ablative. It often describes customary diet rather than one act of eating, and therefore appears frequently in ethnography, natural history, and elevated narrative.

An authentic (formal) example from Sallust (Iugurtha 89.7) describes a people’s diet:

The quotation follows an unmacronized edition; pedagogical forms elsewhere use macrons. In neutral everyday Latin, edō with an accusative is often more direct for consuming a particular item: mālum edit “he eats an apple.” Vēscor mālō instead construes the food as what one feeds on. The two verbs differ in valency as well as nuance.

What the ablative is—and is not

Traditional grammar calls this an instrumental ablative: the subject acts or benefits through the associated thing. That history helps explain the shape, but in Classical Latin the construction is lexical government. A learner must know which verb licenses it.

Compare:

The noun’s real-world identity has not changed; its syntactic relation has. Nor does passive-looking morphology force passive syntax. Ūtitur means “uses,” fruuntur “enjoy,” and fūnctus est “performed.” See What Deponent Verbs Are for the voice system.

Historical and non-finite exceptions

Early Latin sometimes treats these verbs as transitive and uses an accusative. Isolated accusatives also occur in Classical poetry and marked prose, and later usage varies. Such forms are (archaic), (literary), or otherwise exceptional; they do not justify an accusative as a productive pattern in ordinary Classical prose composition.

Their gerundives can also be personal as though the verbs were transitive: rēs ūtendae “things to be used.” This is a real formal exception created by the verbal adjective, not evidence that finite ūtor normally takes an accusative. It belongs chiefly to (formal) prose and legal-administrative language.

Parsing and production diagnostics

1. Identify the verb from its principal parts; do not mistake a deponent form for a passive.
2. Check whether it is one of the five or a compound that retains their government.
3. Parse the associated noun as ablative even when English makes it a direct object.
4. For potior, test the attested genitive alternative, especially rērum.
5. Translate idiomatically only after parsing: “use,” “enjoy,” “perform,” “seize,” and “feed on” are normal English active verbs.

Word order does not change valency. Hōc gladiō ūtor and ūtor hōc gladiō both contain an ablative complement.

Common Mistakes

1. Copying the English direct object

2. Translating the perfect as passive

3. Extending the rule to every deponent

4. Rejecting the genitive with potior

Key Takeaways

Learn ūtor, fruor, fungor, potior, and vēscor with an ablative complement, not by copying the English direct-object pattern. Their compounds usually retain the same government, while potior also has a genuine genitive alternative. Deponent morphology gives these verbs passive-looking forms with active meaning; it does not by itself explain case government, which is lexical and must be learned verb by verb.