How do you spell the word poisoness?

Answer 1

(The informal spelling "poisoness" would be a feminine form of "poisoner," one who poisons.)

The correct spelling of the adjective is poisonous(harmful, venomous).

Answer 2

The likely word phonetically is the adjective poisonous(causing harm, venomous).

Answer 3

It appears you are trying to spell the word poisonous.
An example sentence is "don't eat these berries because they are poisonous".