# The correct usage of every (other/second/third/fourth etc.)

According to the Collins Dictionary's definition:

If something happens every other day or every second day, for example, it happens one day, then does not happen the next day, then happens the day after that, and so on. You can also say that something happens every third week, every fourth year, and so on.

It would mean that if I see my friend today, then tomorrow a one-day-break, then the day after tomorrow I see her and it continues the same way, I can say each one of the sentences below interchangeably:

1.a. I see my friend on alternate days.
1.b. I see my friend every other day.
1.c. I see my friend every second day.

Also, if I see my friend today, then tomorrow and the day after tomorrow a two-day-break, then after two days I see her again and it continues the same way, I can say each one of the sentences below in an interchangeable way without any difference in meaning:

2.a. I see my friend every two days.

Or

I don't know if second is used here or in the former meaning (I mean: on alternate days)?

2.b. I see my friend every second day.

If "every second" is used in the meaning of "on alternate", then here I must use "every third":

2.c. I see my friend every third day.

And the rest is history.

On the other hand, someone else in this thread says:

"Every two days" is the same as "every other day." If you wanted to describe a two-day break, it would be "every third day.

This is what is not clear either in the similar thread on the forum, or in the Collins's definition.

I'm not entirely sure what the question is, but I see no problem with 1a,1b,1c.

2a, and 2b however:

if I see my friend today, then tomorrow and the day after tomorrow a two-day-break, then after two days I see her again and it continues the same way, I can say each one of the sentences below in an interchangeable way without any difference in meaning

A two day break, and then seeing the friend on the day after, is every third day, (one day in three).

Every second day means a 2 day cycle, which is every other day

So 2c would be correct. (and that other thread would be correct too)

Attempting to be clear:

Every day with a visit = 1 day cycle = every single day = every day

One day empty, one day with a visit = 2 day cycle = every second day = once every two days = every other day

Two days empty, one day with a visit = 3 day cycle = every third day = once every three days

Three days empty, one day with a visit = 4 day cycle = every fourth day = once every four days

(the once can usually be omitted)

• If I'm nit mistaken @Smock, based on your statements, every other = every second and every two... = every third. Also, every three = every fourth. Do you confirm? Sep 17, 2019 at 13:44
• No, and I'm not sure how you've read it that way. Just count the total number of days involved. 3 days with one visit is every third day. 2 days with a visit on one of the days is every two days Sep 17, 2019 at 13:49
• Also, saying "I see my friend one day in three" is not the same as "every three days." "Every three days" is a repeating pattern, while "one day in three" means that for each period of three days, you saw your friend only one, but not necessarily the same day each period. Sep 17, 2019 at 13:57
• Please have a look on the picture @Smock. Sep 17, 2019 at 14:22
• @A-friend Picture 2 is not correct, at least for US usage of "every two days". Sep 17, 2019 at 14:58