Glossary
semicolon
A semicolon joins two independent clauses without a conjunction, and separates list items that already contain commas.
A semicolon does one job between sentences and one job inside lists. Between clauses, it stands where a full stop could stand: the material on each side must be an independent clause, and the semicolon says the two thoughts are closely related. The dressing was dry; the site was clean. It cannot be followed by a coordinating conjunction — the dressing was dry; and the site was clean is wrong, because the conjunction alone needs a comma — and it cannot join a clause to a phrase. Its other job is sorting a list that has commas inside its items: the tray held gauze, 4 × 4; tape, one roll; and saline, 10 mL. Without the semicolons a reader cannot tell where one item ends. It is never a comma with extra weight, and never a substitute for a colon, which introduces rather than joins.
Taught in
Related terms
- run-on sentence — A run-on sentence joins two independent clauses with no punctuation at all, while a comma splice joins them with only a comma.
- clause — A clause is a group of words with its own subject and verb; an independent clause can stand as a sentence, a dependent one cannot.
- comma splice — A comma splice joins two independent clauses with only a comma; a comma is not strong enough to hold two sentences together, so one of four repairs is needed.
Source: The grammar guide in this course, whose conventions follow the US Government Publishing Office's Style Manual for standard written American English, with standard grammar references for agreement, case, tense and sentence structure. The GPO manual is US federal government material, not subject to copyright in the United States. Every definition and example above was written for this course; no reference text is reproduced. (GPO Style Manual accessed 2026-10-27; definitions written 2026-10-27)