The word that best fits the definition "The first word in an organism’s scientific name" is Genus.
What is scientific name?
Scientific name of an organism is a standardized way of identifying and naming species.
- The scientific name is usually written in Latin and is composed of two parts: the genus and
- the species.
This system of naming is called binomial nomenclature. In a scientific name, the genus is the first part and is always written with an initial capital letter.
Thus, the word that best fits the definition "The first word in an organism’s scientific name" is Genus. and the genus and species form the complete scientific name for an organism.