Definition of "prattle"

And as E. Rushmore Coglan prattled of this little planet I thought with glee of a great almost-cosmopolite who wrote for the whole world and dedicated himself to Bombay.

1906, O. Henry, A Cosmopolite in a Café

I looked across at Anna, and I noticed that her eyes had grown strangely blank, without expression. I felt instinctively that the subject brought up by Victor was one she would not have chosen. Victor, insensitive to this, went prattling on.

1952, Daphne Du Maurier, “Monte Verità”, in The Apple Tree

Mere prattle without practice is all his soldiership.

c. 1603–1604 (date written), William Shakespeare, “The Tragedie of Othello, the Moore of Venice”, in Mr. William Shakespeares Comedies, Histories, & Tragedies […] (First Folio), London: […] Isaac Iaggard, and Ed[ward] Blount, published 1623, [Act I, scene i], line 27