It means "very good/nice". It's something people said some generations ago, and now people only say it half in jest. It's been relegated, along with "Capital!" "Ace!" "Bully!" "Ripping good show, old sport!" EXAMPLE In the words of Richard Maltby: "Well well, ain't it swell doing swell with the swells in the swellest hotel of them all!" "To swell" also means "to increase in size or number" EXAMPLE "The penguins swelled their numbers this season." "His chest swelled with pride."

Swell a few meanings. It can mean "good," as in "That's just swell!" However, this kind of phrase is barely used anymore and is out-dated, in fact. The more common meaning is "to become larger." For example: A result of injury: "My eye began to swell when I was hit in the face with a baseball." To increase in volume: "The bag swelled more and more as people placed their donations inside." To increase in intensity: "The man swelled with pride as he watched his son on stage during his graduation ceremony." Here are just a few examples of this word. If you have any other questions, let me know.