Definitions

1. adjective

Relating to or containing arsenic, a highly toxic chemical element.

“The arsenious compounds found in the soil posed a significant threat to the local ecosystem.”

2. noun

A salt or compound containing arsenic.

“Arsenious oxide was used as a pigment in medieval art.”

3. adverb

In a manner relating to arsenic.

“The reaction was arsenious in nature, releasing toxic fumes into the air.”