Searching for the big-race winner: Just pick a name that will look right on the roll of honour

It is frequently stated that a good horse never has a bad name, particularly a Derby winner. A glance down the Blue Riband roll of honour shows this to be not entirely true - among 18th and 19th century heroes Waxy, Lapdog, Spaniel, Macaroni and Common are just a few who lack something in nobility and Noble, Eager, Champion, Pope and Sam in originality - but it seems that even so, once a horse earns immortality at Epsom, his name acquires a certain ring.

Except for the winner in 1797, of course. He made his debut in the Derby, raced only once afterwards, and was known merely as the Fidget colt.

Compulsory naming is a relatively recent phenomenon; horses older than two could run un-named until 1913 and anonymous two-year-olds until 1946.

Of course, the naming of a racehorse is entirely subjective and it is an owner's prerogative to call the beast whatever he or she likes, within the bounds of decency and the modern limit of 18 letters and spaces. Which means that the 1849 winner would be called Theflyingdutchman if he was around today.

The art of nomenclature has provided some neat examples through the Classic centuries; in the Derby, for instance, Call Boy (by Hurry On out of Comedienne); in the Oaks, Quashed (Obliterate-Verdict), in the St Leger, Royal Lancer (Spearmint-Royal Favour).

Of the colts running today, some thought has gone into Sir Percy, who is by Mark Of Esteem out of Percy's Lass. There is not only a link though his dam, by Blakeney, but also through his sire, for Sir Percival was honoured as the purest of the Round Table knights. Other of his ilk to have won Derbys have been Sir Peter Teazle (1787), Sir Thomas (1788), Sir Harry (1798), Sir Bevys (1879), Sir Hugo (1892), Sir Visto (1895) and Sir Ivor (1968).

Many of the Aga Khan's horses are called for towns or states in Muslim countries and today's favourite, Visindar, sounds like another. But in fact the colt, by Sinndar out of Visor, was bought already-named in the fusion style typical of his breeder, the late Jean-Luc Lagardère. Other composite Derby winners have been Persimmon (St Simon-Perdita), Orby (Orme-Rhoda B), Crepello (Donatello-Crepuscule), Relko (Tankerko-Relance) and Grundy (Great Nephew-Word From Lundy).

There is generally a theme each year at Ballydoyle; this season's three-year-olds are mostly famous figures. An American president, George Washington, has already won the Guineas; this afternoon it may be the turn of an English admiral, a Welsh poet or a Roman general to strike. Septimus's bay coat is dark in hue; his namesake was the first black emperor of Rome, who died in AD211 in York, so perhaps the colt's Dante Stakes victory there was not inappropriate.

Linda's Lad is more prosaic, a tribute to his owner's daughter's boyfriend. The only young man successful in a Derby to date has been Windsor Lad in 1934. Championship Point is so called because he is owned by a tennis fanatic. Snoqualmie Boy, by Montjeu out of Seattle Ribbon, takes his name from the eponymous mountain resort town near Seattle, in Washington state.

The only initial letters absent from the list of Derby winners are U, X and Z. V is rare enough - there have been only Voltigeur and Volodyovski - and there have been only one each of I (Iroquois), Q (Quest For Fame) and Y (Young Eclipse). S is easily the most popular, with 41 representatives.

With England playing today, it might be interesting to note that two of today's Derby field - Dylan Thomas and Snoqualmie Boy - were born on 23 April, St George's Day. The oldest runner is Before You Go (born on 12 January) and the youngest Atlantic Waves (2 May).

Lady Beaverbrook was in the habit of giving her horses one-word, seven-letter names because that was the composition of most Derby winners. But since her day eight letters has become the mode, 45 of them. So, a dignified, eight-letter name beginning with S? It looks like Septimus.