Canada balsam

noun
1.
a pale yellow or greenish, slightly fluorescent, clear, viscous, bitter-tasting, water-insoluble liquid, having a pleasant, aromatic, pinelike odor, and solidifying on exposure to air: obtained from the balsam fir, Abies balsamea, and used chiefly for mounting objects on microscope slides, in the manufacture of fine lacquers, and as a cement for lenses.
Also called Canada turpentine, balsam of fir.
Origin
1810-20, Americanism
British Dictionary definitions for Canada balsam

Canada balsam

noun
1.
a yellow transparent resin obtained from the balsam fir. Because its refractive index is similar to that of glass, it is used as an adhesive in optical devices and as a mounting medium for microscope specimens
2.
another name for balsam fir
Encyclopedia Article for Canada balsam

oleoresin consisting of a viscous yellowish to greenish liquid exuded by the balsam fir of North America, Abies balsamea. It is actually a turpentine, belonging to the class of oleoresins (natural products consisting of a resin dissolved in an essential oil), and not a balsam.

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