If I want to describe two things happening at the same time, I can use the words parallel or concurrently. In some cases, simultaneously would also work. More suggestions are available in the opposite question, already answered.

In technical writing, most of the time, it is sufficient to identify a process or thread that is parallel; a lack of parallelism is assumed in absence of specificity. But in some cases, the ordinary expectation for something is parallel, so the reverse requires denotation.

The word sequentially implies some of the same things as concurrently. But I'd really like a word that denotes the opposite and can be used in the same way as concurrently.

Here's a few examples:

• "That procedure runs concurrently, so the system doesn't wait for it to finish before moving on."

• "That procedure runs ???, so the system waits for it to finish before moving on."

• "The math library does all of its processing concurrently, so matrix multiplication is faster on a multi-core machine."

• "The math library does all of its processing ???, so it doesn't matter how many cores you have."

• "The backup runs concurrently with the import, so the system doesn't experience any downtime."

• "The backup runs ??? with the import, so the system will be down until it completes."

The audience can assumed to be reasonably technical, though not necessarily domain experts in multithreaded programming. (Bonus points if the word is also useful as a part of function names while programming.) This question is very well straddling the line between here and StackOverflow, but its more about English than programming, I think.

So, does the word I want exist?

If I want to describe two things happening at the same time, I can use the words parallel or concurrently. In some cases, simultaneously would also work. More suggestions are available in the opposite question, already answered.

In technical writing, most of the time, it is sufficient to identify a process or thread that is parallel; a lack of parallelism is assumed in absence of specificity. But in some cases, the ordinary expectation for something is parallel, so the reverse requires denotation.

The word sequentially implies some of the same things as concurrently. But I'd really like a word that denotes the opposite and can be used in the same way as concurrently.

Here's a few examples:

• "That procedure runs concurrently, so the system doesn't wait for it to finish before moving on."

• "That procedure runs ???, so the system waits for it to finish before moving on."

• "The math library does all of its processing concurrently, so matrix multiplication is faster on a multi-core machine."

• "The math library does all of its processing ???, so it doesn't matter how many cores you have."

• "The backup runs concurrently with the import, so the system doesn't experience any downtime."

• "The backup runs ??? with the import, so the system will be down until it completes."

The audience can assumed to be reasonably technical, though not necessarily domain experts in multithreaded programming. (Bonus points if the word is also useful as a part of function names while programming.) This question is very well straddling the line between here and StackOverflow, but its more about English than programming, I think.

So, does the word I want exist?