Select the most appropriate synonym of the given word.
Toxic

To find the most appropriate synonym for the word Toxic, let's examine the definition of the given word and compare it with the provided options:

1. Understanding the target word:
Toxic means poisonous, harmful, or deadly to living organisms.

2. Analyzing the options:
• Lethal: means sufficient to cause death; harmful or destructive. This is highly synonymous with "toxic" as both imply a capacity to cause severe harm or death.
• Licit: means conforming to the law; legal or authorized. This is unrelated to toxicity.
• Laudatory: means expressing praise or commendation. This is unrelated to toxicity.
• Lanky: means ungracefully thin and tall. This is unrelated to toxicity.

Therefore, the most appropriate synonym for "Toxic" is Lethal.