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Describing cell morphology is a tricky task, prone to misinterpretation due to subjective nature of the human observer and his vocabulary limitations. Consequently, these limitations actuate prevalence of non-formalized, statistically unverifiable language use. This determines the reason for overlooking cell shape as a viable parameter for describing cell's functional state intricacies. In this study we demonstrate the use of mathematical parameters set for describing two-dimensional fractals, such as: convex hull, density, roundness and asymmetry, for comparative in vitro morphological analysis of sprawled starfishes' Aphelasterias japonica and Patiria pectinifera (Echinodermata: Asteroidea) coelomocytes, and bivalve's Callista brevisiphonata (Mollusca: Bivalvia) hemocytes. We found that these parameters allow us to describe visually distinguishable but verbally indescribable "chaotic" sprawled cell shapes. Furthermore, resulting numerical cell descriptions differs significantly, enabling for their species-specific grouping and classification. We argue that presented morphometric methodology can be used for describing and classifying cells of any arbitrary morphology, as well as compiling "cell shape - cell functional state" match library for later use in in vitro analysis, potentially for cells of any animal.