We have defenestration in Portuguese too, and also Spanish. Probably in french too since "fenestre" (window), the source of the word, is in french.
In English, one of the longest words is a specific kind of lung disease: pneumonoultramicroscopicsilicovolcanoconiosis. It even passes the spell-check on Firefox. But I guess it's not entirely pointless, just pointlessly long.
We have that word too. In every neolatin language.
German has some fun ones... "Schadenfreude" (enjoying someone else's pain).
Portuguese has "saudade" (to miss someone), though it's not quite pointless.