All Blackfoot nouns are classified as animate or inanimate. This distinction is marked by the different singular and plural endings on the noun. Take a look at the nouns matápii ‘person’ and áípottaa ‘airplane’.

For matápii, the ending -wa indicates that it is singular and -iksi indicates that it is plural. For áípottaa, the ending -yi indicates that it is singular and -istsi indicates that it is plural. The endings are different because matápi is an animate noun and áípottaa is an inanimate noun. See the section on number for more information.

All animate nouns in the dictionary have a category label that starts with na. All inanimate nouns in the dictionary have a category label that starts with ni. There are a few nouns that can be either animate or inanimate, or where the animacy is not certain. These indeterminate nouns have a category label that starts with nx. The labels are found in the entry bar immediately following the Blackfoot word.