Verbosity, or verboseness, is speech or writing that uses more words than necessary. The opposite of verbosity is succinctness.^{[dubious – discuss]}

Some teachers, including the author of The Elements of Style, warn against verbosity. Similarly Mark Twain and Ernest Hemingway, among others, famously avoided it.

Synonyms of "verbosity" include wordiness, verbiage, loquacity, garrulousness, logorrhea, prolixity, grandiloquence, expatiation, sesquipedalianism, and overwriting.

The word verbosity comes from Latin verbosus, "wordy". There are many other English words that also refer to the use of excessive words.

Prolixity comes from Latin prolixus, "extended". Prolixity can also be used to refer to the length of a monologue or speech, especially a formal address such as a lawyer's oral argument.

Grandiloquence is complex speech or writing judged to be pompous or bombastic diction. It is a combination of the Latin words grandis ("great") and loqui ("to speak").

Logorrhea or logorrhoea (from Greek λογόρροια, logorrhoia, "word-flux") is an excessive flow of words. It is often used pejoratively to describe prose that is hard to understand because it is needlessly complicated or uses excessive jargon.

Sesquipedalianism is a linguistic style that involves the use of long words. Roman poet Horace coined the phrase sesquipedalia verba in his Ars Poetica. It is a compound of sesqui, "one and a half", and pes, "foot", a reference to meter (not words a foot long). The earliest recorded usage in English of sesquipedalian is in 1656, and of sesquipedalianism, 1863.