Do you speak Latin? If the answer is no, you may have trouble with some abbreviations derived from that language, such as i.e., e.g, or et al. Let’s focus on one of these: et al. You may have seen it, but it’s time to find out what exactly it means and how to use it.
Et al. is an abbreviation for et alia (neuter plural), et alii (masculine plural), or et aliae (feminine plural). This phrase means “and others.” Imagine that you and a group of friends decide to publish some anecdotes from your most recent trip to Las Vegas. If you have ten members in your travel club, you can imagine that listing all of them on the cover of a book might look a little cluttered. To avoid a lengthy list, you can use the abbreviation et al. after the first name. Et al. indicates that two or more other authors collaborated in the work.
When people cite the work of you and your friends, they would likely use et al., especially in formal writing such as term papers and on works cited pages. Here are two examples, one in-text mention of a publication and another from a works cited page:
These linkages were monitored by large-scale correlational survey research (e.g., Coleman et al., 1966) and subsequent reanalyses of that data set (Jencks et al., 1979 and Mosteller & Moynihan, 1972).
Holt, John. “How Teachers Make Children Hate Reading.” The Norton Reader, 13th Edition. Ed. Linda Peterson, et al. New York: W.W. Norton, 2012. 195-203
In the first example, the writer uses parenthetical notations to refer to materials that he used as references. His first resource was a research study published by seven contributors. Rather than list everyone, he credits his source by using the name of the principal investigator, James S. Coleman. The second example shows how a publication with multiple editors would appear in a bibliography.
Are there synonyms of et al.? Yes. According to The Cambridge Dictionary, also, extra, and in addition are synonyms with similar meanings to et al.
Et al. is also short for a less frequently used Latin phrase, et alibi. Can you guess the meaning of et alibi? An alibi is a piece of evidence that shows a suspect of a crime was elsewhere when the crime happened. So, it’s not hard to remember that et alibi means “and elsewhere.” Mainly, et alibi refers to other locations that will not appear in a list. Consider the following example from a Greek grammar guide by William Trollope. He uses et alibi to indicate that the Greek phrase under consideration appears not only in the sixth chapter of Mark but also in other locations of the Bible.
The [Greek phrase] to make a feast (Mark VI. 21, et alibi) is of course anarthrous.
Isn’t it great news that you and your friends can publish about your vacation together without filling the cover with a comprehensive list of names? You can use et al. to acknowledge numerous authors. And if you begin talking about different locations, the list of casinos and hotels need not be exhaustive. You can also let your readers know about the existence of other places with et al. Then again, do you really want to let the world know about what happened in Las Vegas?
from Grammarly Blog https://www.grammarly.com/blog/what-is-the-correct-use-of-et-al/