The Hebrew word for ten is eser עשר (and the masculine form is asarah עשרה). Does this number derive from an earlier word?

Klein follows the BDB, and writes about the root עשר:

The orig. meaning of this base prob. was 'gathering, collection, union'. cp. Arab. 'ashara (= he formed a community), 'ashirah ( = tribe), ma'ashar (=a group of ten men). Accordingly, Heb. עשר (eser), Arab. 'ashr, etc. prob. meant orig. 'a group collection', whence 'a group of ten', and ultimately 'ten'.

Rav Hirsch (Bereshit 14:20) follows the same line of thought, and mentions that other similar sounding roots also have related meanings: אסר, אצר, עצר, אזר, עזר.

Steinberg, in Milon HaTanach, has a different theory. He says that עשר is related to עצר, meaning "to stop". He therefore writes that eser got it's name because it is where you "stop" counting (when you're counting on your fingers.)

Strong takes a slightly different approach. He writes:

A primitive root (ident. With ashar); to accumulate

Should we accept the connection with the words ashir עשיר - wealthy, and osher עושר - riches? At first we might reject this approach because one has the letter sin and the other has the letter shin. But we can see here that many Semitic languages have the "sh" sound in their word for ten: esher in Akkadian, `asharah in Arabic.

So to determine if there is a connection, we should use Horowitz's advice (and Lonnie's Biblical Hebrew teacher's), and see how each term is used in Aramaic.

Sometimes how you define a word actually "defines" you as well.

For example, let's take the Hebrew words nesher נשר and ayit עיט.

From an informal survey I have taken, most native English speakers (who know Hebrew) will identify the nesher with the eagle, and if they have an answer - the ayit with the vulture.

Israelis, on the other hand, generally reverse the definitions. If they know English - they'll say nesher = vulture, and ayit = eagle. For those that didn't know, I showed them this picture:

The Israelis would usually say that #1 is an ayit, and #2 is a nesher.

Typically, the modern commentaries reflect this division. The JPS translates nesher as eagle, for example in Shemot 19:4, where the translation "on eagles' wings" sounds much more natural than "on vultures' wings" (82,000 hits on Google for the former vs. 7 for the latter.) On the other hand, the Daat Mikra almost always identifies the nesher with the Griffon Vulture.

The dictionaries also know their audience. The Even-Shoshan Dictionary (Hebrew-Hebrew) has the Griffon Vulture as the primary definition for nesher, with eagle as only a secondary option. Even-Shoshan also has eagle for ayit. The Alcalay Dictionary (Hebrew-English) has exactly the opposite order.

But of course, there are always those people who take it upon themselves to correct popular usage and put the masses on the proper path. And here we find two articles - each trying to convince the reader that they should change their initial association.

First we find an article by Rabbi Nosson Slifkin - no stranger to controversy. In his article, The Identity of the Nesher, he tells an English speaking audience why they should think of vultures, not eagles, when they say nesher.

Here are some of his reasons: