noun

1. Stubbornness.

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

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.

Synonyms: adamant, contrary, disobedient, headstrong, insubordinate, obdurate, obstinate, rebellious