# What is the term for years 2005,2010,2015,1990 in general?

I am wondering if there is any term to call years which are the multipliers of 5 or 10 like 1990, 2000,2005,2015,... in English.

We informally call them "round years" in Finance but I hope to know the commonly-used word for this.

In a specific context "Your doctor tells you to have a test the following year, and thereafter, every round year." So, can I ask what does round years here mean? Does it mean 2025,2030,2035 ?

• "round years" would get your point across informally in my opinion, but wouldn't provide any kind of accuracy (some people would think of "round" as meaning 10, others 100, others a multiple of 2) May 10, 2021 at 10:35
• I don't think there's a word for that. You could say ‘years that are multiples of 5’.
– Void
May 10, 2021 at 10:49
• Or "years evenly divisible by five". May 10, 2021 at 14:15
• In a specific context "Your doctor tells you to have a test the following year, and thereafter, every round year." So, can I ask what does round years here mean? Does it mean 2025,2030,2035 ? May 10, 2021 at 21:16
• Is the that specific context a quote, or something that you made as an example May 10, 2021 at 21:35

There is no specific term, or at least no commonly understood term. (There is a very rare term "pentad" or "pentade". I'd never heard it until now, so don't use it.)

The phrase "Round numbers" is like "large numbers". There is no standard definition of "large number", but we all know that 10 is larger than 8, and 1000000000000 is a large number in most contexts. Similary 2000 is rounder than 2010.

We don't often talk about "round years" but if we did I'd guess it would usually mean 1990, 2000, 2010. These are numbers that have been rounded to the nearest 10.

If your doctor wants to be understood precisely then she can't use "round years" because this doesn't have a precise meaning. Most likely she would say "Have a test next year and then every five years" (the numerical value of the year doesn't matter, but the spacing does). If the numerical value of the years does matter, she could say "in the first and fifth year of each decade". (Although literally this is 2000, 2004, 2010 2014. So some longer description is needed. "at the start and in the middle of each decade" or something similar.)

The company is audited each year, but (twice a decade/every five years), an in-depth audit takes place. However the 2020 audit was cancelled due to COVID restrictions. So the next in-depth audit will look at the whole period from 2015 to 2025.

• "Every first and fifth year of a decade" is intended to be a spacing of 5-5-5-5 between years but is really 4-6-4-6. "First and fifth" could be interpreted to mean either "x0 and x4" or "x1 and x5" but what you mean is "x0 and x5." Here I would take the side of the pedants who say that the new millennium started January 2001, and use "every fifth and tenth year of each decade." May 10, 2021 at 22:03
• For what it's worth, I would interpret "the first and fifth year of each decade" as meaning "years ending in 0 or 4," or possibly as "years ending in 1 or 5," but definitely not as "years ending in 0 or 5" unless the context made it clear that the former two interpretations are clearly and certainly not intended. May 10, 2021 at 22:04
• The millenium started in 2001 (if you want) but the decade started in 2020 (ob xkcd. But you are right that that gives 0,4,0,4 if taken literally May 10, 2021 at 22:27