Meaning of "chevalet" in the English dictionary

The Berkley Horse is a BDSM apparatus, supposedly designed for, or by, Theresa Berkley in 1828. She referred to it as a "chevalet". According to the account of Henry Spencer Ashbee: A notorious machine was invented for Mrs Berkley to flog gentlemen upon, in the spring of 1828. It is capable of being opened to a considerable extent, so as to bring the body to any angle that might be desirable. There is a print in Mrs Berkley's memoirs, representing a man upon it quite naked. A woman is sitting in a chair exactly under it, with her bosom, belly, and bush exposed: she is manualizing his embolon, whilst Mrs Berkley is birching his posteriors. He continues: When the new flogging machine was invented, the designer told her it would bring her into notice, and go by her name after her death; and it did cause her to be talked of, and brought her a great deal of business. The original horse is among the models of the Society of Arts at the Adelphi, and was presented by Doctor Vance, her executor.