every third day

USAGE SUMMARY

The phrase "every third day" is correct and commonly used in written English.
It means something happens or occurs every third day, or every three days. Examples: 1. She goes for a run every third day to maintain her fitness levels. 2. We have our weekly team meeting every third day, on Wednesdays. 3. The museum is closed for maintenance every third day.

✓ Grammatically correct

Science

News & Media

Human-verified examples from authoritative sources

Exact Expressions

60 human-written examples

Cultures were kept for up to 10 days with medium changes every third day.

Archives of Toxicology

Pellet cultures were cultivated for 21 days with medium change every third day.

BMC Veterinary Research

P. redivivus were cultured for 12 days, and 3% HB101 was added every third day.

Analytical Chemistry

Every third day was chosen to reduce autocorrelation between concentrations on successive days, while maintaining power.

Environmental Health Perspectives

One milligram of Estradiol every third day.

The New York Times - Health

The medium was replaced in this manner every third day.

Nature

In situ oxygen uptake rates were measured at the tailings surface every third day, prior to sampling.

Journal of Contaminant Hydrology

Re-charging of batteries is only needed every third day.

European Transport Research Review

Instrumental evaluations of skin colour were performed after each cream application (every third day).

Chemistry Central Journal

The medium was changed every third day and MSCs were maintained at 37 °C, 5% CO2.

European Radiology Experimental

The water exchange rate was approximately 50%% of the tank volume every third day.

International Aquatic Research

Expert writing Tips

Best practice

When describing schedules or routines, clearly specify the starting point to avoid ambiguity about which days the action occurs. For instance, "Starting Monday, the medication should be taken every third day."

Common error

Avoid assuming "every third day" means three times a day. It indicates an action repeats with a two-day gap in between. If something happens three times a day, specify "three times daily" or "three times a day".

Linguistic Context

The phrase "every third day" functions as an adverbial phrase modifying a verb, specifying the frequency or interval at which an action or event occurs. It indicates a recurring action with a consistent two-day gap. As Ludwig AI confirms, this construction is grammatically sound and widely used.

Expression frequency: Very common

Frequent in

Science

78%

News & Media

18%

Formal & Business

4%

Less common in

Encyclopedias

0%

Wiki

0%

Reference

0%

Ludwig's WRAP-UP

In summary, the phrase "every third day" is a grammatically correct and commonly used adverbial phrase that specifies an action or event occurring with a two-day interval. Ludwig AI validates its correct usage. It's frequently found in scientific and news contexts, serving to provide temporal precision. Alternative phrasings include "every three days" or "once every three days". Remember to clearly define the starting point when using this phrase to avoid ambiguity. The high frequency and varied source types confirm its wide acceptance in both formal and informal communication.

More alternative expressions

Phrases that express similar concepts, ordered by semantic similarity:

every three days

Uses a different numerical expression to convey the same frequency.

once every three days

Adds emphasis on the single occurrence within the interval.

every 72 hours

Specifies the interval in terms of hours, providing a more precise timeframe.

at three-day intervals

Rephrases using 'intervals' to highlight the recurring gap in time.

tri-diurnally

Uses a less common, formal adverb to indicate the frequency.

every third rotation of the Earth

More descriptive, literally counting days as Earth rotations.

on alternate days, skipping one

Describes the pattern by specifying what is skipped.

every other day, then skip one

Clarifies the pattern by explicitly mentioning skipping a day.

three days apart

Focuses on the separation between occurrences.

a three-day cycle

Presents the occurrence as part of a repeating cycle.

FAQs

How can I use "every third day" in a sentence?

You can use "every third day" to describe recurring events or actions. For example: "The plants need watering every third day" or "The medication should be taken every third day."

What is another way to say "every third day"?

Alternatives to "every third day" include "every three days", "once every three days", or "at three-day intervals".

Is it correct to say "every three day" instead of "every third day"?

No, the correct phrasing is "every third day" or "every three days". "Every third day" indicates a specific interval, while "every three days" means the same thing but emphasizes the duration.

What is the difference between "every other day" and "every third day"?

"Every other day" means something happens with one day in between, whereas "every third day" means it happens with two days in between. Therefore, "every second day" is a synonym for every other day.