Cecil Wormsborough St. John "Nobby" Nobbs is a fictional character in the Discworld novels of Terry Pratchett. He is a corporal in the Ankh-Morpork City Watch, first appearing in the novel Guards! Guards!.

Nobby Nobbs is the kind of person who joins the army to loot corpses. It is said that there's a field-marshall's baton in every footman's knapsack; Nobby's Army kit generally consists of two warehouses, complete with said batons, other armies' uniforms, golden teeth, other petty valuables and several kilos of boots, some of them still occupied. Despite his kleptomania, he is honest about the big things (at least, the ones too big to steal) and is described as someone that you can trust with your life, although you'd be daft to trust him with half a dollar. Sgt Colon also remarked in Jingo that he had heard of places where the generals looked at which side's uniform Nobby wore at the moment to learn the situation of the battle.

He is described as untidy, smelly, and despite being human, about the same height as a dwarf, and carrying a certificate signed by the Patrician to prove that he's a human being. The text of this note can be read in Feet of Clay (page 270 in the UK paperback) and states that on the balance of probability, he is a human being. A running joke is the inability of others to believe this, despite — or even because of — the evidence. In fact, in Hogfather, even Death himself was unable to discern Nobby's species. He always seems to have a cigarette butt about him, normally stowed behind his ear, which has been described as a nicotine graveyard. Cigarettes quickly become butts in his presence, and stay as such for an apparently infinite amount of time.

Samuel Vimes is Nobby's commanding officer, and Sergeant Fred Colon his partner and longterm friend. Together, Nobby and Colon have managed to have many strangely philosophical (or just strange) conversations, including one on whether Death has a first name, or even any friends to call him it. Oddly enough, these conversations hint at Nobby being more intelligent than Colon, with Nobby continually pointing out fatal flaws in Colon's statements and arguments, and Colon mentally scrambling to come up with an answer.

As a child he was a street urchin, that is, small, prickly, and smelling of fish, and a major source of information for various city notables. He was apparently inspired to join the Watch after meeting with Sergeant-At-Arms John Keel (and alternatively, due to time travel, Sam Vimes), who once gave him a spoon.

Nobby was once thought to be the Earl of Ankh, but it was all a charade to make him king. Nobby proved less tractable than the conspirators had expected, turning down a cushy life as figurehead ruler of Ankh-Morpork largely, by his own account, for fear of what Vimes would have to say when he found out. However, at the end of the book Feet of Clay, it is also suggested that he may be a real nobleman, due to the amount of family heirlooms he has not mentioned to any other person. On the other hand, the Nobbses have stolen so much stuff over the years that, as Vimes has said, you could probably prove Nobby was the Dowager Duchess of Quirm.

Nobby played a role in the resolution of the "war" between Ankh-Morpork and the empire of Klatch in Jingo, and in recognition the Patrician gave him a new job in traffic control. He has since been "promoted" to assistant to the Watch Liaison Officer (in other words Fred Colon), a job vague enough to ensure he never has to do anything actually important.

He believes he is in a romatic relationship with Verity "Hammerhead" Pushpram, a girl who runs a fish stall and gets her nickname from the fact that her eyes appear to be looking in opposite directions. However, this "relationship" seems to consist solely of her hitting him with a fish and telling him to bugger off. He remains "faithful" to her, however, in all books except Thud!, in which he is temporarily in a relationship with exotic dancer Tawneee.

He is possibly related to Corporal Knopf (as Knopf can be translated as knob), one half of the town watch in Bad Blintz, Überwald, seen in The Amazing Maurice and his Educated Rodents. Other Discworld characters with a notable similarity to Nobby include a member of the guard in the Überwald town of Bonk, who was nicknamed "Nobbski" by Vimes, and one of the market guards in Al Khali, Klatch. Like the various Dibblers, this may be due to morphic resonance.

According to Men At Arms, Nobby was 'disqualified from the human race for shoving'