living being; living creature
A somewhat formal or literary term for a living organism, often used in contrast to inanimate objects or in philosophical/biological contexts.
Many living creatures inhabit this forest.
I think about the difference between living beings and inanimate objects.
parasite; parasitic organism
Compound of 活 (katsu, 'living, active') and 物 (butsu, 'thing'). The exact historical derivation is uncertain, but the spelling is conventionally associated with the meaning 'living being'.