Word for the *other* day in a two-day cycle

Question

My son's school operates on an A-day, B-day schedule, i.e. on a two-day cycle. Some classes meet every day, and some meet every other day, perhaps on A days, perhaps on B days. I need a word or a phrase to say the following:

Right now you have your science lab in Period 7 every other day. Let's ask if they'll let you do your foreign language in that slot on the other days.

I need a better word than other. Opposite comes to mind but I'm not sure if people will understand it. (School personnel are less sophisticated than you guys.)

Also, consider

But I'm not sure if they'll allow you to attend foreign language half time.

Is there something better than half time? Obviously, every other day would work, but in these conversations, I get really tired of saying "every other day" over and over again. Will people understand "half time"?

There is a thread about this where bidiurnal was suggested but that's too sophisticated for the school and for me.

If you need to rewrite my sentences slightly I am open to that.

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Edit: I will experiment with DJClayworth's idea of replacing "every other" in Sentence 1. Here goes.

(DJ inspired) Right now you have your science lab in Period 7 on a half schedule. Let's ask if they'll let you do your foreign language in that slot on the other days.

Now I will try using the suggestion in the comment, alternate:

Version (a): Right now you have your science lab in Period 7 on alternate [or alternating] days. Let's ask if they'll let you do your foreign language in that slot on the other days.

Version (b) (playing further with DJ's idea): Right now you have your science lab half time in Period 7. Let's ask if they'll let you do your foreign language in that slot on the alternate days.

Answer 1

I believe the answer your looking for is off days. I don't know if the term is as common in other countries besides America. However, this can be confused with the same term given in several dictionaries as "having a bad day/game" (particular to sports).

Answer 2

If you stick to names, rather than relative descriptors, I think most of your troubles will disappear. In high school, my schedule (or timetable as we would say) had a 6 day cycle. Each day in the cycle was named after the day, so we had day 1, day 2 and so on. We always referred to days by their name, so, we would say the following:

Right now you have your science lab in Period 7 on day 1. Let's ask if they'll let you do your foreign language in that slot on day 2.

If we had to talk about frequency we would simply say something like this:

But I'm not sure if they'll allow you to attend foreign language on one day only.

The example above may be confusing to a listener unfamiliar with the system, but this didn't tend to be the case. The rewritten statements are also more precise, and less cumbersome than what you would currently say.

Answer 3

Referring to the 'other day' of a two-day cycle is a perfectly acceptable way of writing what you mean. The confusion only arises because you have used the phrase 'other day' to already mean something else. You can probably clear up the confusion by using another term in place of the first 'other day. For example:

Right now you have your science lab in Period 7 on alternate days. Let's ask if they'll let you do your foreign language in that slot on the other days.

Alternatively, in place of 'on alternate days', try:

• every second day
• on the first/second day of the cycle
• on one day of the cycle
• on the A/B day
• of one day

Answer 4

First sentence

I don't know if school personnel will understand it (for the sake of understanding I'm not sure you can do better than other), but the word you are seeking may be intervening.

From the Free Dictionary:

intervening: occurring, located, or present between other things

And your example:

Right now you have your science lab in Period 7 every other day. Let's ask if they'll let you do your foreign language in that slot on the intervening days.

Second sentence

You seem to be implying, without stating it explicitly, that there are foreign language classes every day, but that your son will be able to attend only half of these. If you want to avoid using half time (which isn't that bad), perhaps you could say:

But I'm not sure if they'll allow you to attend only every other foreign language class.

Answer 5

I would offer the word interjacent.

INTERJACENT ADJECTIVE located in between; intervening - Collins Dictionary

Right now you have your science lab in Period 7 every other day. Let's ask if they'll let you do your foreign language in that slot on the interjacent days.