What is a semicolon?

Semicolons might be the most misunderstood and neglected of all punctuation marks. Semicolon usage in literature has dropped sharply in the last century. There used to be a semicolon every ten words; now, you’re lucky to see a semicolon every ten pages. An excerpt from The Time Machine by HG Wells, published in 1895, shows the once-prolific use of semicolons:

Presently, as I went on, still gaining velocity, the palpitation of night and day merged into one continuous greyness; the sky took on a wonderful deepness of blue, a splendid luminous color like that of early twilight; the jerking sun became a streak of fire, a brilliant arch, in space; the moon a fainter fluctuating band; and I could see nothing of the stars, save now and then a brighter circle flickering in the blue.

And again, in Edgar Rice Burroughs’ A Princess of Mars:

“Princess of Helium, I might wring a mighty ransom from your people would I but return you to them unharmed, but a thousand times rather would I watch that beautiful face writhe in the agony of torture; it shall be long drawn out, that I promise you; ten days of pleasure were all too short to show the love I harbor for your race. The terrors of your death shall haunt the slumbers of the red men through all the ages to come; they will shudder in the shadows of the night as their fathers tell them of the awful vengeance of the green men; of the power and might and hate and cruelty of Tal Hajus. […] Tomorrow the torture will commence; tonight thou art Tal Hajus’; come!”

“That’s crazy!” you might say. “Were all of those semicolons correct? Have I been writing incorrectly this entire time? Are commas really not as multi-purpose as I’ve been led to believe? Do I have to go through countless agonizing punctuation lessons in order to not look like a complete idiot? Where’s my inhaler??”

Don’t fret! Semicolons are simply the misunderstood neighbor of the punctuation neighborhood. Just like the guy who lives next to the sandlot and owns a scary dog, but once you meet him, he’s James Earl Jones, and he gives you a signed baseball.

The correct use of semicolons starts with clauses, conjunctions and commas

To be able to fully understand proper semicolon usage, you must first understand a few other aspects of English grammar: Independent and dependent clauses, conjunctions, and the basics of comma usage.

  • An independent clause is a clause (also known as a sentence) that can stand on its own. In other words, it’s a complete sentence. It needs a subject and a verb at the very least. “The Martian disembarked his spaceship” is an independent clause because it’s a standalone sentence.

  • A dependent clause is a clause that can’t stand on its own, or is not a complete sentence. “Glancing around nervously” is a dependent clause, because there’s no subject; we don’t know who or what is glancing around nervously.

  • Conjunctions are words that we can easily remember with the acronym “FANBOYS:” For, And, Nor, But, Or, Yet, So.

  • As for comma usage, that’s a broad and interesting topic. Understanding the basics of comma usage (but mostly their relationship with conjunctions) is important to understanding semicolon usage.

And now, on to the rules!

Semicolon rules & examples

When to use a semicolon vs. a period

A semicolon is used in place of a period when you want to emphasize a relationship between two sentences. Two independent clauses that aren’t closely related shouldn’t be joined with a semicolon. The semicolon in this sort of construction shouldn’t be linked with a conjunction.

  • Correct: “Now, Professor Hardwigg, my worthy uncle, is by no means a bad sort of man; he is, however, choleric and original.” — A Journey to the Centre of the Earth

  • Incorrect: “Now, Professor Hardwigg, my worthy uncle, is by no means a bad sort of man; I very much enjoy a good game of badminton.”

In both examples, the semicolon joins two independent clauses. If you were to rewrite the second part as, “but he is choleric and unoriginal,” it would become a dependent clause because it wouldn’t be able to stand on its own as a sentence. In that case, you’d replace the semicolon with a comma.

That second example doesn’t make a lick of sense, since your enjoyment of badminton has nothing to do with your uncle being a bad man or not.

When to use a semicolon vs. a comma

Complicated lists that contain commas amongst individual points benefit from semicolons for clarity’s sake.

  • Correct: “I have friends from Tampa, Florida; San Antonio, Texas; and Juneau, Alaska.”

  • Correct: “The President spoke to the press on Monday, the day after he decided he wouldn’t seek a second term; on Wednesday, the day after he changed his mind; and on Friday, when the polls showed a downturn in his popularity rating.”

You can also use a semicolon between two sentences (as in Rule #1) when a comma appears in either sentence. However, this semicolon must be used with a conjunction, unlike the semicolon in Rule #1.

  • Correct: “His cast-iron features puckered into a smile of the richest drollery, and his eyes twinkled with the wickedest fun; but no undignified giggle escaped the portal of those majestic lips.” — A Journey to the Center of the Earth

How to use a semicolon with “However” and other conjunctive adverbs

Examples of conjunctive adverbs include “however,” “therefore,” “namely,” and so on. You can find a list of common conjunctive adverbs here. If the conjunctive adverb is introducing a list, you can use either a comma or a semicolon.

  • Correct: “I scoured my favorite science fiction books for an example; however, I could not find any.”

And that’s really it! To recap, a semicolon is used in place of a period when two clauses are closely related; to separate a very complicated or long list; and with a conjunctive adverb.

That wasn’t so bad, was it? This is what the poet Lewis Thomas had to say of this, the most feared punctuation on earth:

I have grown fond of semicolons in recent years…. It is almost always a greater pleasure to come across a semicolon than a period. The period tells you that that is that; if you didn’t get all the meaning you wanted or expected, anyway you got all the writer intended to parcel out and now you have to move along. But with a semicolon there you get a pleasant little feeling of expectancy; there is more to come; read on; it will get clearer.

Several of the links below on semicolon usage also have quizzes you can take to see if you really “get” semicolons. Go for it!

Here’s your signed baseball, kid.

Further Reading