Yielding to the temptation to try and untwist that long-suffering thread, let me modestly mention that "participle" stems from "participere", i.e. taking part in both the world of verbs and the world of adjectives. Furthermore, an adjective can be used in an attributive sense: "The red apple fell from the tree." or in a predicative sense: "The apple is red". Now if you say: "the politician was (is) ousted", it is arbitrary to consider "ousted" a form of a verb or an adjective in predicative use: it is a participle. The attributive use of participles is more restricted: You can say: "the bike was thrown into the canal", but as for "The thrown bike.." I am not so sure..