General Uses of Ūsus, -ūs

As a (fourth declension masculine) noun, ūsus can adopt a variety of closely-related but powerfully particular meanings:

1. Ūsus + genitive typically refers to the use, exercise or enjoyment of something.

  • ūsus ocūlōrum: eyesight
  • ūsus pectōrālis : push-ups
  • ūsus unguentis: the delights of cologne (I highly recommend getting this at TJ Maxx—half-price!)

2. On its own, ūsus can either refer to ‘exercise’ or ‘wear and tear’

  • Fidēs nōn ad ūsum tendit: the insurance does not cover wear and tear.
  • Musculōsa ūsū cotidiānō exstitit: she became very buff through daily exercise
  • (the more straightforward exercitātiō is more common, at least in my experience)

3. It can also reference a ‘habit’ or social ‘custom’

  • ūsum loquendī populō concessī; scientam mihi reservāvī: I have give up my habit of making speeches to the people, but I have retained my habit of learning (Cicero in old age)
  • populum auctōritāte suā ad ūsum frūgalitātis vocāvit: by his authority, he brought the people to a habit of moderation (Lycurgus)

Some Latin Dry Measures: Visual Dictionary

I recently came across the modius and trimodius measures in Plautus, and became curious about what exactly I should imagine. They’re dry measures, typically of grain, but they are also roughly equivalent to a peck and a bushel (bzw.), so we can illustrate them with apple baskets, since it’s Fall—



photo credit: Wikimedia

Here’s a peck, a.k.a a modius.


photo credit:

Here’s a bushel, which is four pecks (a little more than a trimodius).

Imagine what this basket would look like after the slave helped himself to a few…. that’s a trimodius.

Ūsus est maiōre usū

The phrase ūsus est + ablative is the rarer counterpart to the well known opus est + ablative, signifying need.


  • Nunc vīribus ūsus est: now there is need of strength.
  • Quid istīs cōnscrīptīs ūsust: what is the use of getting these in writing?

Ūsus vēnit is another still rarer alternative.

The Essential AG: 411


Uses of Ambō

Ambō is sometimes decline to match its respective noun, like a fully-functional adjective, but otherwise remains fixed as ambō

  • Ambās mānūs lavit: he washed both hands.
  • Consulēs alter ambōve prōgredientur: either one or both of the consuls will march on
  • ūna salus ambobus erit: both were healthy (this is Virgil—a very Greek declension!)

Effectively, there is no rule. Both A&G and L&S present freeform variation between the two options.