The term 'bitter feeling' can be described by four words with 8, 5, 3, and 7 letters respectively: ACRIMONY, SPITE, IRE, and illwill. ACRIMONY is a strong feeling of resentment or bitterness, often expressed in a hostile manner. SPITE is a feeling of malice or ill will towards someone, usually expressed through hurtful words or actions. IRE is a strong feeling of anger or displeasure. Illwill is a feeling of hostility or animosity towards someone. All of these words describe a negative emotion that is felt towards someone or something.