Definition of "inflexion"

[…] I do not like the studied air and artificial inflexions of voice which your very popular and most admired preachers generally have.

c. 1803–1805, Jane Austen, “The Watsons”, in J[ames] E[dward] Austen[-]Leigh, A Memoir of Jane Austen: […] to which is Added Lady Susan and Fragments of Two Other Unfinished Tales by Miss Austen, 2nd edition, London: Richard Bentley and Son, […], published 1871, page 338