He authored and is best known for the Novo Dicionário da Língua Portuguesa ("New Dictionary of the Portuguese Language"), first published in 1899 and then republished in twenty-five editions through 1996.
Perhaps his best known fictional book is Lisboa no ano 3000 ("Lisbon in the year 3000"), a work first published in 1892 (and recently reedited and rereleased) which critiqued Portuguese society and institutions of the era.
Figueiredo eventually abandoned the priesthood—a profession apparently forced on him by his family—obtaining a pro gratia dismissal from the clerical state from Pope Leo XIII.
In 1876 he settled in Lisbon, opening a law office there in partnership with fellow University of Coimbra alumnus Júlio de Vilhena [pt], who later became a famed jurist.
In 1893 Cândido de Figueiredo was appointed civil governor of Vila Real District by then Prime Minister of Portugal José Dias Ferreira.
His work was published in various Portuguese periodicals of his time, including O Panorama [pt], Aljubarrota, Lusitano, Progresso, Bem Público, Voz Feminina, Revista dos Monumentos Sepulcrais, Almanaque de Lembranças, Notícias (which would later become Diário Popular), Grinalda, Crisálida, País, Hinos e Flores, Repositório Literário, Tribuno Popular, Independência, Recreio Literário, Folha, Panorama Fotográfico, Viriato, Gazeta Setubalense, Democracia (published in Elvas).
He also contributed stories and collaborated with various magazines, including Revista de Portugal e Brasil, Ocidente, República das Letras (1875), Ribaltas e Gambiarras (1881), A Arte Musical (1898-1915), O Branco e Negro (1899), Serões (1901-1911), Atlântida (1915-1920), and even in the humorous publication A Paródia (1900-1907) under the pseudonym "O Caturra".