Acidulous

Origin

From Latin acidulus ("sourish, acidulous"), diminutive of acidus ("acid, sour"). See acid.

Adjective

adjective

1. Slightly sour; sub-acid; sourish.
• Edmund Burkean acidulous tincture
• 1931: He talked with acidulous tolerance of the exalted personages who had sent Ashenden to X. -- William Somerset Maugham, His Excellency