Rhetoric has a bad reputation nowadays. It usually occurs in such phrases as “false rhetoric” or “misleading rhetoric”, suggesting that it is an old-fashioned word for what is now known as “spin”.

Yet for centuries, rhetoric was not only respected highly but formed an essential element of education. Its study arose in the 4th century BC, when Aristotle wrote his On Rhetoric. Aristotle and other pioneers of rhetoric (like Cicero and Quintilian) believed that you could teach people how to speak, or write persuasively, and the Sophists set up schools of rhetoric in fifth-century Athens.

From the Middle Ages onwards, education was based on the seven liberal arts, which were divided into the Quadrivium (arithmetic, geometry, astronomy and music) and the Trivium (rhetoric, grammar and logic). The concept of the liberal arts explains why we call some university graduates “Bachelor of Arts” or “Master of Arts”.

“Rhetoric” was still a subject at some schools and universities until comparatively recently. I A Richards wrote in The Philosophy of Rhetoric (1936): “Rhetoric . . . is the dreariest and the least profitable part of the waste that the unfortunate travel through in Freshman English.” And Rhetoric is apparently still the name of the top class at the Roman Catholic school Stonyhurst College.

Rhetoric did not mean misleading oratory but simply effective communication: the handling of words to express yourself clearly or even eloquently. In this sense, it comes close to what we now more often call “style”. And it embraces what we call “figures of speech”: devices to make our communications more effective, persuasive, or eloquent.

Figures of speech comprise anything that deviates from straightforward expression. So “The cat sat on the mat” is a straightforward statement, but it is more vivid if we add a simile: “The cat sat on the mat like a ball of black wool”.

The simile and the metaphor are probably the figures of speech which most people know. As E M Forster said: “Only connect” and we often make connections between things when writing, or speaking. We use similes which make comparisons — “He is like a bear with a sore head”; “You look as pretty as a picture”, or we leave out such words as “like” and “as” to create metaphors “He’s a bear in the mornings”; “She’s an English rose”.

Metaphors are probably the commonest figures of speech in English. In fact many individual words got their present meaning through metaphors. The word ponder comes from a Latin root that meant “to weigh”; explain originally meant “to spread out”; postpone comes from two Latin words meaning “to place after”; and attract meant to draw towards someone.

We often use metaphors without being aware of it — for example, when we resort to idioms like pave the way, sift the evidence and one foot in the grave. The biggest danger in metaphors is found in “mixed metaphors”, where images are used that conflict with one another. The most notorious example occurred in a speech attributed to the politician Sir Boyle Roche: “Mr Speaker, I smell a rat; I see him forming in the air and darkening the sky; but I’ll nip him in the bud.”

There are a lot more figures of speech besides metaphors and similes. Henry Peacham’s Garden of Eloquence (1577) enumerated nearly 200 figures, including bomphiologia, hypotiposis, prosographia, sermocinatio and topothesia.

However outlandish these words may appear, Peacham listed many figures of speech that we still use today. For example, there is metastasis, which Peacham says occurs “when we turn back those things that are objected against us, to them that laid them unto us”. For example, “Talk about greedy! Who ate all the pies?”

Even if you did not realise it, you have probably used synecdoche, where part of something is substituted for the whole, such as calling your car your ‘wheels’. You may even have used epizeuxis, the emphatic repetition of a word: “It was Tony Blair — yes — Tony Blair, who caused all the trouble”. And few people can boast that they have never resorted to hyperbole — ‘He’s the greatest!’ Antonomasia is the name for that figure of speech in which we substitute an epithet for someone’s name, like calling Shakespeare “The Bard”, or we use a proper name to evoke a particular characteristic “A Daniel come to judgement!”

Anaphora, or symploce, is the term for another commonly used rhetorical device: repeating one or more words or phrases for emphasis: “Where there is hatred, let me sow love; Where there is injury, pardon . . .”

My favourite figure of speech mentioned by Henry Peacham is zeugma, which I somehow remember from my schooldays. The OED defines it as: “A figure by which a single word is made to refer to two or more words in the sentence; esp. when properly applying in sense to only one of them, or applying to them in different senses.” The example which is inexplicably imprinted on my mind is “She left in tears and a sedan chair.”

Tony Augarde is the author of The Oxford Guide to Word Games (OUP, £14.99) and The Oxford A to Z of Word Games (OUP, £4.99)