1 (abbreviation: sp., spp.) Biology a group of living organisms consisting of similar individuals capable of exchanging genes or interbreeding. The species is the principal natural taxonomic unit, ranking below a genus and denoted by a Latin binomial, e.g., Homo sapiens.
Logic a group subordinate to a genus and containing individuals agreeing in some common attributes and called by a common name.
a kind or sort:a species of invective at once tough and suave
used humorously to refer to people who share a characteristic or occupation:a political species that is becoming more common, the environmental statesman
Chemistry & Physics a particular kind of atom, molecule, ion, or particle:a new molecular species
2 Christian Church the visible form of each of the elements of consecrated bread and wine in the Eucharist.
late Middle English: from Latin, literally 'appearance, form, beauty', from specere 'to look'
The plural of species is the same as the singular. Remember that the ending is -ies.