slightly sour or acidic, not strongly so, often describing a mild tanginess

acidulo, lievemente aspro

too confident or proud in expressing oneself, in a way that is annoying to others

presuntuoso
(of some plants or animals) having sharp, needle-like things on the surface of their body

spinoso, acuminato

extremely evil or wicked, typically involving illegal or immoral actions

nefando, infame

keeping the title of their former position after retirement as an honor, especially of a university professor

emerito, professore emerito

(of animals and plants) found and developed only in a particular place and not been brought from elsewhere

indigeno
characterized by excessive ingratiation or flattery, often in a way that seems insincere or manipulative

untuoso, appauntato

