stubborn

ot noun

1. Stubbornness.
2. A disease of citrus trees characterized by stunted growth and misshapen fruit, caused by Spiroplasma citri.

sifat adjective

1. Refusing to move or to change one's opinion; obstinate; firmly resisting; persistent in doing something. Blood can make a very stubborn stain on fabrics if not washed properly.
2. Of materials: physically stiff and inflexible; not easily melted or worked.