The word butter derives (via Germanic languages) from the Latin butyrum, which is the latinisation of the Greek (bouturon). This may have been a construction meaning "cow-cheese", from (bous), "ox, cow" + ? (turos), "cheese", but perhaps this is a false etymology of a Scythian word. Nevertheless, the earliest attested form of the second stem, turos ("cheese"), is the Mycenaean Greek tu-ro, written in Linear B syllabic script. The root word persists in the name butyric acid, a compound found in rancid butter and dairy products such as Parmesan cheese. In general use, the term "butter" refers to the spread dairy product when unqualified by other descriptors. The word commonly is used to describe pureed vegetable or seed & nut products such as peanut butter and almond butter. It is often applied to spread fruit products such as apple butter. Fats such as cocoa butter and shea butter that remain solid at room temperature are also known as "butters". In addition to the act of applying butter being called "to butter", non-dairy items that have a dairy butter consistency may use "butter' to call that consistency to mind, including food items such as maple butter and witch's butter and nonfood items such as baby bottom butter, hyena butter, and rock butter. A false etymology (pseudoetymology, paraetymology or paretymology), sometimes called folk etymology although this is also a technical term in linguistics, is a popularly held but false belief about the origins of specific words, often originating in "common-sense" assumptions. Such etymologies often have the feel of urban legends, and can be much more colorful than the typical etymologies found in dictionaries, often involving stories of unusual practices in particular subcultures (e.g. Oxford students from non-noble families being forced to write sine nobilitate by their name, soon abbreviated to s.nob., hence the word snob). Many recent examples are "backronyms" (acronyms made up to explain a term), as in "snob", and "posh" for "port outward, starboard homeward"; many other sourced examples are listed in the article on backronyms. Erroneous etymologies can exist for many reasons. Some are reasonable interpretations of the evidence that happen to be false. For a given word there may often have been many serious attempts by scholars to propose etymologies based on the best information available at the time, and these can be later modified or rejected as linguistic scholarship advances. The results of medieval etymology, for example, were plausible given the insights available at the time, but have mostly[citation needed] been rejected by modern linguists. The etymologies of humanist scholars in the early modern period began to produce more reliable results, but many of their hypotheses have been superseded. Even today, knowledge in the field advances so rapidly that many of the etymologies in contemporary dictionaries are outdated.