English Language & Usage Stack Exchange is a question and answer site for linguists, etymologists, and serious English language enthusiasts. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I think many people here are programmers since stack sites started out as stackoverflow originally, which is about programming.

My question here is about the phrasal verb "to comment out". It makes a lot of sense to those who know that in programming you can easily turn some part of the code (usually a line) into simply a comment that would have no bearing on the code's execution. For example,

print: Hello world 

can be easily turned into a comment in this way:

; print: Hello world  

Programmers would say in this case, "I have commented out the line." It is absolutely logical and makes sense to me. However, I wonder if this phrasal verb ever was used before the programming came about. Did it exist in those times? If yes, in what situation it was normally used then?

share|improve this question
up vote 3 down vote accepted

As far as I can tell from a few minutes searching on Google Books, comment out has not been used as a phrasal verb other than in the programming sense.

Here's the most interesting use of the collocation:

1689   Abednego Seller, The History of Passive Obedience Since the Reformation 97   We have ſeen Rebellion commented out of Rom. xiii.

Since Romans 13 is all about obedience ("Let every soul be subject unto the higher powers ...") I think this must be comment used in the obsolete sense "devise, contrive, invent" [OED].

share|improve this answer
WOW!!! That's just amazing! Thank you. – brilliant Aug 25 '12 at 2:40
Umm ... I think you've got hold of the right sense of comment; but if you look at the passage Seller is quoting, it's clear that commented out of means justified on the factitious basis of Rom.xiii. – StoneyB Aug 27 '12 at 22:05

I have never encountered this usage outside programming, and there's no reason to expect it would have existed before then.

"Commenting out" means instructing the compiler or interpreter to ignore the text in question. The primary purpose of incorporating the instruction was to allow the programmer to insert comments which would make his code more intelligible - what you might now, if you were as frivolous as I, distinguish as "commenting in". Programmers quickly realized, however, that the instruction also permitted them to de-activate code segments for test or debugging purposes, and it is that which is the origin of "commenting out".

No such practice is called for in ordinary literary texts. Comments of various sorts may be distinguished "in line" through puncutation or a change of script or type; or inserted in margins or at the foot of a page; or banished to the end of a text. Deletions are accomplished by, well, deletion, or overstriking, or excision.

share|improve this answer
The term is also sometimes used when talking about documentation and XML/HTML files (e.g. web pages). These uses post-date and (I assume) derive from the programming usage, but it's not just a programming term any more. – Monica Cellio Aug 24 '12 at 14:59
You say compiler and interpreter as though those were somehow different things. :) An assembler will also ignore comments. This suggests room for another word altogether. – tchrist Aug 24 '12 at 15:02
@tchrist Perhaps usage has changed since I was a programmer in the '80s. Then a compiler translated code into a freestanding executable program, while an interpreter translated and executed code line by line; a compiler was thus just a more sophisticated assembler. – StoneyB Aug 24 '12 at 15:08
@StoneyB Yes, it doesn’t really work that way anymore, apart from shell scripts and batch jobs and the like. Most so-called “interpreted” programming languages first compile into some form of intermediary code, like p-code or byte code, and turn that over to either an interpreter (execution runtime) directly, or pass it through a code-generation phase to produce machine language to pass to the firmware interpreter. Essentially, all code is both compiled and interpreted. Uncompiled p-code has no comments left, because the compiler doesn’t pass those to the interpreter. Interpreters get none. – tchrist Aug 24 '12 at 15:13
@tchrist thank you. Please feel free to edit my answer for forward-compatibility. – StoneyB Aug 24 '12 at 16:08

Perhaps there is a similar verb to commenting out for non-programming settings, but "Comment Out" derives directly from the fact that you are using the comment syntax to remove something. The semicolon in your example wasn't originally intended to remove data, it was intended to allow programmers to make comment in their code for future reference.

Without the reference point of the commenting code syntax, the term "Comment Out" would hold no meaning.

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.