Emily Dickinson Lexicon

SAN'GUINE, or SAN'GUIN, a. [Fr. sanguin; L. sanguineus, from sanguis, blood.]

1. Red; having the color of blood; as, a sanguine color or countenance. – Dryden. Milton.
2. Abounding with blood; plethoric; as, a sanguine habit of body. [Technical.]
3. Warm; ardent; as, a sanguine temper.
4. Confident. He is sanguine in his expectations of success.