[f. as prec. + -ORIUM: cf. L. scriptōrium, etc.] A compressor; spec. an instrument used in microscopical research by which a graduated pressure may be brought to bear on the object under examination.
1845. Todd & Bowman, Phys. Anat., I. 168. To steep it in weak acetic acid, and then to thin it out, under the compressorium.
1867. J. Hogg, Microsc., I. iii. 195. Compressorium.—The purpose of this instrument is to apply a gradual pressure to objects whose structure can only be made out when they are pressed or thinned out by extension.
