When the Two Become One – Ever-Evolving Compounds

Two words brought together to express a new concept create a compound. A compound can be written as two words, one word, or it can be connected by a hyphen.

Many times compounds will evolve over time. For example, a compound may start out as child care, morph into child-care and finally it’s more commonly written as childcare.  

The use of hyphens in compounds can sometimes be confusing. Here are some general guidelines for using hyphens in compounds:

• Use a hyphen when two or more words are used as an adjective before a noun.

                        over-the-counter drugs                         

                        six-year-old boy

                        one-way street

• Do not use a hyphen when the compound modifier comes after the noun.

                        The boy is six years old.

                        I bought the drugs over the counter.

                        The street is one way.

• Use a hyphen with compound numbers.

                        Sixty-five

                        Twenty-one

• Use a hyphen to avoid confusion.

An old-furniture salesman means the man sells old furniture. However, “an old furniture salesman” could be an old man who sells furniture.

On the other hand, the phrase “used car salesman” might not generate as much confusion, therefore, a hyphen between “used” and “car” might not be necessary.

As you can see, sometimes there are no hard and fast rules when it comes to compounds. Since word usage often evolves, it’s always best to consult the latest version of a good, standard dictionary.