The word 'Toxoplasma' is a modern scientific Latin construction, directly borrowing its components from ancient Greek. The first element, 'toxo-', originates from toxikon, a term for poison used on arrows, which itself derives from toxon (bow). This reflects the organism's pathogenic, or "poisonous," nature. The second element, '-plasma', comes from the Greek plassein, meaning to mold or shape, referring to the flexible, moldable form of the single-celled organism. Thus, the name literally means "poison-shaped (organism)," logically describing its toxic, parasitic character and its amorphous, plastic structure as it invades host cells.

Structure: toxo (poison) + plasma (something formed or molded) - toxo: From Greek toxon (bow) and later toxikon (poison for arrows). In modern scientific use, it denotes poison or toxicity. - plasma: From Greek plasma (something molded or formed), from plassein (to mold). In biology, it refers to living substance or formative material.