Definition of "milkshake"
milkshake
/ˈmɪlk.ʃeɪk/
noun
plural milkshakes
(slang, horse racing) An alkaline supplement administered to a horse to improve its racing performance.
verb
third-person singular simple present milkshakes, present participle milkshaking, simple past and past participle milkshaked
(transitive, slang, horse racing) To administer an alkaline supplement to (a horse) to improve its racing performance.