[ kwat-er ]
/ ˈkwæt ər /
Save This Word!

(in prescriptions) four times.
Should you take this quiz on “shall” versus “should”? It should prove to be a quick challenge!
Question 1 of 6
Which form is used to state an obligation or duty someone has?

Origin of quater

From Latin
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2022


What does quater mean?

Quater is a Latin term used in medical prescriptions to mean four times, typically in the Latin phrase quater in die, meaning “four times a day.”

Quater in die is sometimes abbreviated as q.i.d.

Example: The pill is to be taken quater in die—that means four times a day.

Where does quater come from?

Uses of quater meaning “four” are recorded in English as far back as the 1600s. But today its use is limited to a Latin phrase that is usually (hopefully) translated into plain English as “four times.”

When the pharmacist gives you the medicine that has been prescribed by your doctor, they provide instructions for how to take it, such as how many times per day, and with or without food. The medical field uses Latin for all kinds of technical terms, and many pharmaceutical notations are also based on Latin terms, such as per os for “by mouth.”

If you see quater in die or q.i.d. on your medicine bottle, you’ll know you need to take it four times a day—hopefully because it also says “take four times a day.”

Similar notations include quaque die (q.d.) for “every day,” bis in die (b.i.d.) for “twice a day,” and ter in die (t.i.d.) for “three times a day.”

Did you know ... ?

What are some synonyms for quater?

  • four times

What are some words that share a root or word element with quater?


What are some words that often get used in discussing quater?


What are some words quater may be commonly confused with?



How is quater used in real life?

The word quater is used pretty much exclusively in prescriptions and other medical contexts.


Try using quater!

If your prescription says to take it quater in die, how many times should you take it in one day?

A. 1
B. 3
C. 4
D. 8

How to use quater in a sentence