The term 'poison' can be defined as a substance that causes harm or death when ingested, inhaled, or absorbed through the skin. Crossword solutions for this term include INFECTION (9 letters), CONTAMINATION (13 letters), BLIGHT (6 letters), BAD (3 letters), VENIN (5 letters), TOXIC (5 letters), RAT (3 letters), IVY (3 letters), OAK (3 letters), PEN (3 letters), BANE (4 letters), SUMAC (5 letters), TAINT (5 letters), TOXIN (5 letters), and VENOM (5 letters). INFECTION refers to the invasion of a host organism by a pathogen, such as a virus, bacteria, or fungus, which can cause illness or death. CONTAMINATION is the process of making something impure by contact with or addition of a poisonous or polluting substance. BLIGHT is a plant disease caused by fungi, bacteria, or viruses, which can cause stunted growth or death. BAD is an adjective used to describe something that is of poor quality or has negative effects. VENIN is a TOXIC substance found in the saliva of certain animals, such as snakes. TOXIC is an adjective used to describe something that is poisonous or harmful. RAT is a rodent that is known to carry diseases. IVY is a climbing plant that can cause skin irritation and other health problems if touched. OAK is a type of tree that can produce acorns, which are poisonous to humans. PEN is a tool used to write with, but it can also be used to refer to a prison cell. BANE is a noun used to describe something that causes harm or ruin. SUMAC is a type of shrub that produces a poisonous oil. TAINT is a verb used to describe the process of making something impure or corrupt. TOXIN is a poisonous substance produced by living organisms. VENOM is a TOXIC substance produced by certain animals, such as snakes, that can cause serious injury or death.