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What is the difference between fox and box versus ox, that the first two are pluralized as foxes and boxes, whereas the last one is pluralized oxen?

Note: I know how to pluralize them. What I want to know is what makes them different from each other, why they are pluralized as they are.

Joking: the plural of box is boxen. [Kudos to Mark for that first link]

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Related reading: lingwe.blogspot.com/2009/02/… –  Geobits Jun 20 at 19:35
The -en was already being used on fox in vixen, as a feminine suffix, with umlaut (o->i) and initial voicing (f->v). –  John Lawler Jun 20 at 19:39
Or rather: u > y > i. The "o" in "fox" is secondary. –  fdb Jun 20 at 22:47
Note that "boxen" is a plural of "box". –  Mark Jun 21 at 3:41

3 Answers 3

up vote 14 down vote accepted

The word ox comes from the Old English oxa. In Old English, as in Indo-European languages in general (historically and even today), the number of a noun (singular or plural) and its function in a sentence—whether it was the subject, direct object, indirect object, or had some other relation to a verb or another noun—was largely (not solely) governed by sets of endings tacked onto it, or changes made to the vowels in it. These sets of endings or changes were called declensions, and each type of relationship associated with an ending is called a case.

There were a number of declensions in Old English; the two most prominent were the weak declension, containing the weak nouns, and the strong declension, containing the strong nouns. Old English oxa was a weak noun. The forms that we have of its descendant today are derived from the nominative case endings; these are the forms that would indicate that a noun is the subject of a sentence, or the forms that would be used when writing a list of nouns.

Since oxa was a weak noun, its plural form (the nominative plural form) was oxan. Over the course of centuries, the a "weakened" to an e, giving us oxen.

Fox, on the other hand, comes from the Old English fox, which was a strong noun; its Old English plural was foxas, whence we get foxes.

The source I used to confirm the declension of fox has an entry for the Old English box; however, it has no declension information. Using this translator, however, it appears that the nominative plural was boxas, giving us boxes.

Although Modern English has largely dropped the declensional suffixes we got from Old English, we occasionally see them peeking through, as we do here.

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One might also consider our other two remaining vestiges: child > children and brother > brethren (although the latter is now restricted to spiritual, ecclesiastical, or professional relationships). Note also how the stressed vowel changes upon inflection in those two words, but does not do so in ox > oxen. I would like to know more about that disparity myself. –  tchrist Jun 22 at 18:33
I found some interesting statements in etymologies of "child"; I'll ask the question if you haven't already. –  Matt Gutting Jun 24 at 13:11
I’ve looked no further than the OED etymology entries. –  tchrist Jun 24 at 13:25
Thank you very much, for your answer and for your clarification thereof! –  AnotherUser Jun 29 at 4:59
Is there anything that decides whether a noun is "weak" or "strong"? ....if not, then all we did was just push the question back a few hundred years+ (if Old English ended circa 1150).... –  AnotherUser Jun 30 at 4:26

My guess is that it has to do with word origin. The proto-Germanic word for oxen was ukhson so the ending didn't move too much. Meanwhile "fox" comes from "fukhs" which followed words like "box" to the es ending.

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Actually, *uhson (or *uhsō, more likely) was the PG for ox, not oxen. The PG plural was probably *uhsniz. Both had been somewhat refashioned by the time of Old English. –  Janus Bahs Jacquet Jun 20 at 21:11

Sometimes you have two systems in a language. Traces of an old system, and a newer system that is more regular and easier. Oxen is a plural form of the old system. In German, where you have a relatively irregular plural formation with several endings and vowel change as an extra difficulty, we have still the plural form Ochsen, singular der Ochs.
Compared to German, the English plural system with the ending -s/-es is easy apart from a handful of plural forms that stem from the old system and which in most school books are labeled as exceptions.

Although the English plural system is easy, English has developed a new difficulty, nouns that have no plural form because they are uncountable or nouns with identical sg and pl form and a lot of other numerus particularities.

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