Why did Georges Friedel use the name nematic for one liquid crystal phase?

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liquid crystal Figure 1: Arrangements of molecules.

The French scientist Georges Friedel coined the term nematic in the 1920s to describe a specific phase of liquid crystals.

The name is derived from the Greek word for "thread." This nomenclature was inspired by the appearance of these substances under a microscope; when investigators observed the nematic phase, they noted threadlike images caused by defects in the alignment of the molecules' directors—the axes along which the molecules are oriented. Unlike the layered structure of the smectic phase, the nematic phase is characterized by molecules that are disordered in position but possess a common orientation, resulting in these distinct, threadlike visual patterns.12