Definition of "undissembled"

I ſavv the reſpectful Dovvncaſt of his Eye, vvhen you catcht him gazing at you during the Muſick: He, I vvarrant, vvas ſurpriz'd, as if he had been taken ſtealing your VVatch. O! the undiſſembled Guilty Look!

1722, Richard Steele, The Conscious Lovers. A Comedy. […], London: […] J[acob] Tonson […], published 1723, Act II, scene i, page 37

He paid me the most high-flown compliments; and frequently and forcibly seized my hand, though I repeatedly, and with undissembled anger, drew it back.

1778, Fanny Burney, Evelina: Or the History of a Young Lady's Entrance into the World, Letter LXVIII: EVELINA TO THE REV. MR. VILLARS. Clifton, Sept. 28th.

[…] and which, in every part of it, was full of grace and truth: that is, conspicuously distinguished by the most amiable condescension, and benignity of disposition and manners, and by the most undissembled and inviolable sincerity.

1815, Samuel Stanhope Smith, A Comprehensive View of the Leading and Most Important Principles of Natural and Revealed Religion, page 198

I write to-night lest my delay appear tedious to the dear and deserving object of my most undissembled love.

1835, Jonathan Going, J. F. Schroeder, J. M. Krebs, J. Tackaberry (editors), Memoirs of Rev. Samuel Pearce, in The Christian Library, Volumes 3-4, page 376