clostridia

/K L AO1 S T R IH1 D IY0 AH0/
noun
  1. 1

    Any of several mostly anaerobic gram-positive bacteria, of the genus Clostridium, that are present in the soil and in the intestines of humans and animals and are capable of forming spores

Source: https://en.wiktionary.org/wiki/clostridia, https://en.wiktionary.org/wiki/clostridium