Words such as "airplane," "newspaper," or "paperclip," contain two distinct words that function separately but have been placed together. Joining these two independent words creates a compound word, which may have a new meaning or simply a more precise definition. "Air" and "plane" come together to form "airplane," while "paper" and "clip" become "paperclip." These words can be formed either as a solid term or using a hyphen; non-standard phrases are often created as descriptive words or adjectives.
Meaning and Purpose
A compound word is, simply, two words joined to make a new and often more specific word applicable to a particular circumstance. For instance the word "news" can mean many things, though it usually refers to the delivery of current information. When combined with the word "paper," which could also refer to several different things, the compound word, "newspaper," is formed and refers to a specific object. Similarly, a "paperclip" is a particular type of clip intended for a specific purpose.
Typical Usage
It is important to understand the use of compound words because some of them may have different definitions when the words are joined, rather than merely used consecutively in a sentence. This distinction is vital to ensuring proper meaning in a statement. For example, the compound word "overall" takes on a slightly different meaning than the two words "over all" in a sentence.
This can be seen in the two following sentences: "Overall, I enjoyed the film," and "The film was picked over all the others to win an award." In the first example, "overall" is a transitional word that sums up the thoughts of the speaker. It could be used as a synonym for terms like "in conclusion." In the second example, however, the words "over all" imply "above all the others" or "over all the others;" this usage means something is superior to something else, rather than a summation.
Basic Structure
When someone joins two words together to form a compound word, the spelling of those words does not usually change. Instead, the major change is simply a deletion of spaces between the words. It is, in essence, a marriage of words, where two become one.
There are some exceptions to this rule of marriage. Just as many women prefer a hyphenated last name when they get married to keep their maiden names, some compound words may be hyphenated instead of being joined directly together. Compound words not joined by a hyphen are called "closed" compounds, while words joined by a hyphen are "hyphenated" compounds. There is also an "open" form for a compound word such as "post office," in which the space is not deleted but the two words function as one.
Hyphenated and Closed Compounds
When choosing whether to join words, either by hyphen or deletion of space, a writer should consult a dictionary for the correct structure. There are many words that may be compounded, and sometimes it can be difficult to determine how they should be joined and in what context it is appropriate to do so. Generally, when someone joins two words that are not usually compounded, the writer uses a hyphen to express a relationship, instead of creating a compound word that does not actually exist. This is often done for words that are used together to create an adjective such as "well-known" or "bright-red."