Forever confusing: lifelong, life-long, life long

Here’s a set of words that have perplexed some writers their entire lives: lifelong vs. life-long vs. life long.

Most grammarists agree that lifelong – meaning lasting through one’s existence, as in a lifelong friendship – should be one word rather than two words or hyphenated.

Confusion over the spelling arises because punctuation rules say that compound words, when used as an adjective, usually require a hyphen, as in well-known man. “Usually” is the operative word here, as lifelong is an exception. The same applies to other “long” words that show a length of time, such as daylong, monthlong, weeklong and yearlong.

Life long is never correct. Typically compound words with a space consist of two nouns, such as ice cream.


My name is Rob Bignell. I’m an affordable, professional editor who runs Inventing Reality Editing Service, which meets the manuscript needs of writers both new and published. I also offer a variety of self-publishing services. During the past decade, I’ve helped more than 300 novelists and nonfiction authors obtain their publishing dreams at reasonable prices. I’m also the author of the 7 Minutes a Day… writing guidebooks, four nonfiction hiking guidebook series, and the literary novel Windmill. Several of my short stories in the literary and science fiction genres also have been published.