Eureka (word)
The exclamation 'Eureka!' is attributed to the ancient Greek scholar Archimedes. He reportedly proclaimed "Eureka! Eureka!" after he had stepped into a bath and noticed that the water level rose, whereupon he suddenly understood that the volume of water displaced must be equal to the volume of the part of his body he had submerged. (This relation is "not" what is known as Archimedes' principle—that deals with the "upthrust" experienced by a body immersed in a fluid.) He then realized that the volume of irregular objects could be measured with precision, a previously intractable problem. He is said to have been so eager to share his discovery that he leapt out of his bathtub and ran naked through the streets of Syracuse.
Aberri Eguna
"Aberri" is a neologism coined by Sabino Arana based on the suffix "-ba" which occurs in numerous kinship terms (e.g. "osaba" "uncle", "izeba" "aunt", "arreba" "sister of a man" etc.) from which he fancifully deduced a putative root *aba "father". He formed numerous neologisms based on this putative word such as "aberri" (*aba + "herri" "land, people, country, settlement"), "abizen" "surname" (*aba + "izen" "name") or "abenda" "race" (*aba + "enda" "lineage"). From "aberri" he then went on the coin "abertzale" "patriot" ("aberri" "fatherland" + "-(t)zale", a suffix denoting someone keen on something). In spite of their fanciful derivation, "aberri" and "abertzale" have found their way into general usage.