the longest word in Finnish, but evidence of it actually being used is scant and anecdotal at best. Compounds can be rather long when translating technical documents from English to some other language, since the lengths of the words are theoretically unlimited, especially in chemical terminology. For example, when translating an English technical document to Swedish, the term "Motion estimation search range settings" can be directly translated to , though in reality, the word would most likely be divided in two: – "search range settings for motion estimation". Subclasses Semantic classification A common semantic classification of compounds yields four types: endocentric exocentric copulative appositional An endocentric compound (tatpuruṣa in the Sanskrit tradition) consists of a head, i.e. the categorical part that contains the basic meaning of the whole compound, and modifiers, which restrict this meaning. For example, the English compound doghouse, where house is the head and dog is the modifier, is understood as a house intended for a dog. Endocentric compounds tend to be of the same part of speech (word class) as their head, as in the case of doghouse. An exocentric compound (bahuvrihi in the Sanskrit tradition) is a hyponym of some unexpressed semantic category (such as a person, plant, or animal): none (neither) of its components can be perceived as a formal head, and its meaning often cannot be transparently guessed from its constituent parts. For example, the English compound white-collar is neither a kind of collar nor a white thing. In an exocentric compound, the word class is determined lexically, disregarding the class of the constituents. For example, a must-have is not a verb but a noun. The meaning of this type of compound can be glossed as "(one) whose B is A", where B is the second element of the compound and A the first. A bahuvrihi compound is one whose nature is expressed by neither of the words: thus a white-collar person is neither white nor a collar (the collar's colour is a metonym for socioeconomic status). Other English examples include barefoot. Copulative compounds (dvandva in the Sanskrit tradition) are compounds with two semantic heads, for example in a gradual scale (such a mix of colours). Appositional compounds are lexemes that have two (contrary or simultaneous) attributes that classify the compound. Syntactic classification Noun–noun compounds All natural languages have compound nouns. The positioning of the words (i.e. the most common order of constituents