Gilbert Arthur a Beckett (1837-October 15, 1891) was an English writer.
He was born at Hammersmith, United Kingdom, the eldest son of Gilbert Abbott a Beckett. Graduating from Christ Church, Oxford, as a Westminster scholar in 1860, he was entered at Lincoln's Inn but gave his attention chiefly to drama, producing Diamonds and Hearts at the Haymarket in 1867. It was was followed by other light comedies. His pieces include numerous burlesques and pantomimes, the libretti of Savonarola (Hamburg, 1884) and of The Canterbury Pilgrims (Drury Lane, 1884) for the music of Dr. (afterwards Sir) C.V. Stanford. The Happy Land (Court Theatre, 1873), a political burlesque of W. S. Gilbert's Wicked World, was written in collaboration with F.L. Tomline. For the last ten years of his life he was on the regular staff of Punch.
His health was seriously affected in 1889 by the death of his only son, and he died in 1891.