UK, 1881—a form of repetitive strain injury (first identified in tennis players) that affects the tendons of forearm muscles attached to the lateral epicondyle of the humerus—synonym ‘lateral epicondylitis’
early 19th century—chiefly U.S.—to be forced by another to walk on tiptoe—to walk cautiously—to be discharged or dismissed—to discharge or dismiss (someone)—origin unknown
Australia, 1934—an inexhaustible supply of something, especially money—alludes to The Magic Pudding (1918), by Norman Lindsay, in which a pudding instantly renews itself as it is sliced or eaten into
USA, 1946—a feeling of regret experienced after making a purchase—also, in extended use: a feeling of regret experienced after voting for a particular person or programme
UK, 1958—a type of moustache in which the two ends extend downwards to the chin—refers to Emiliano Zapata, who was portrayed with a moustache of this kind by Marlon Brando in Viva Zapata! (1952)
1975 as ‘French chef’s kiss’—a gesture used to indicate that something is excellent or perfect—also a perfect or excellent person or thing—alludes to such a gesture stereotypically made by a chef on tasting a delectable dish
a makeshift incendiary device for throwing by hand, consisting of a bottle filled with flammable liquid and with a piece of cloth as a fuse—Finland, 1940, in reference to Vyacheslav M. Molotov, who led the Soviet campaign against Finland