If prepend is not part of English, why is there no postpend or subpend? And who introduces them? [closed]

I wanted to ask it already for some time but was in doubt until I've read the comment by Stan Rogers to this answer:

In the case of prepend, we have created an artificial term that is meaningless outside of the "in group", since to append means merely to add -- it does not have a positional implication; it can be prepositional or postpositional.

If "prepend"

is not an English word. It was created to sound like the opposite of "append," which means to add to the end. The correct English word is "prefix;

and

Although it sounds correct, prepend is not an English word. It was created to sound like the opposite of "append," which means to add to the end. The correct English word is "prefix;"

then why there are no words "postpend", "subpend", "sidepend", "uppend"?

Who does introduce incorrect words into English which are not English words?

I would use prefix for

prefix_object_suffix

and

prepend,
object,
append

As with any endeavor in life, it is usually best to learn the rules before breaking them.

Prepend arose because append began to mean add to the end rather than merely add in common usage. It would have been correct to say append to the front of the list, but it is increasingly likely that some people would find it confusing. Not to mention that it takes more keystrokes or syllables to do the job "properly" and we all operate on the Principle of Least Effort (that is to say, we're fundamentally lazy).

New word coinages happen all of the time. Some new words become vogue words for a while and quickly fall out of general use. some are useful enough to become part of a group's jargon, but never see any use outside of a specific field. Some are co-opted from jargon into general use. Others just make so much sense (their meaning is obvious and they neatly package a concept that is otherwise difficult to express) that they almost immediately become part of the standard language.

None of this means that you can take a word that has a precise meaning in one context and spring it on the general public with the expectation that they will have any idea what you're saying. If you use a technical term, for instance, it might not help that there are resources that define the term perfectly -- if people don't understand the terms used in the definition, they still won't know what you're talking about. The same thing goes for new coinages. If you make up a word, there's a chance that people won't know what you mean -- but there's also a chance that the meaning is perfectly clear and obvious. (Shakespeare did quite a lot of that, sometimes very successfully, sometimes not.)

One thing to keep in mind is that it's horribly impolite to go breaking into someone else's property and declaring yourself to be in charge. The Humpty Dumpty approach rarely works.

Why there are no words postpend, subpend, sidepend, uppend?

As Robusto’s answer says, words are introduced into English by common usage, at least within some group of speakers.

But one can trace this back further. Why do some words come in to common usage in a group, and not others? There are several factors that can cause a word to catch on:

• They fill a gap in the language.
• They’re easily comprehensible.
• They catch the group’s imagination, by humour, aesthetics, or similar.
• They’re used by people who are seen as ‘cool’ within the group.

Prepend fits both the first two points very well. The gap in the language had appeared because, as Stan Rogers says, append had shifted to mean attach to the end of, no longer just attach to. And the meaning is quite clear: there’s a transparent analogy to append, and the prefix pre- is very familiar.

When there aren’t any strong reasons for a new coinage to catch on, it probably won’t. People will use more familiar words by default.

Why don’t the other words you mention exist?

• Postpend isn’t in wide use, probably because doesn’t fill much of a gap in the language at present: append means roughly the same as postpend would mean. But it’s easily comprehensible, like prepend; so it can quite easily become a word, and in fact it does get used occasionally. Most of these usages are indeed in a case where there’s a clear reason to prefer it to append: they want something that pairs well against prepend.

• Subpend is reasonably clear in meaning (to attach beneath something) but there would rarely be any call for it: I guess you could say you subpend a cedilla to c in ç? But it also has an awkwardness to it: the cluster -bp- is rare for phonological reasons, usually having been assimilated to -pp- (in eg suppose), but suppend wouldn’t work either as it’s less transparent in meaning.

• Sidepend is similar, but worse: more awkward in meaning, since side- is not often used as a verb prefix (sideswipe, …?), and more rarely wanted — when would you want sidepend that you couldn’t just use append?

• Uppend is completely unclear. It’s confusingly close to the word up-end, meaning to turn over, and I’m not even sure what it would mean. Overpend would be a bit more plausible — it’s perhaps close to subpend in comprehensibility.