The Collaborative International Dictionary of English v.0.48:
Glidder \Glid"der\, Gliddery \Glid"der*y\, a. [Cf. Glide.] Giving no sure footing; smooth; slippery. [Prov. Eng.] [1913 Webster] Shingle, slates, and gliddery stones. --R. D. Blackmore. [1913 Webster]