An expressive loan is a loanword incorporated into the expressive system of the borrowing language, making it resemble native words or onomatopoeia. Expressive loanwords are hard to identify, and by definition, they follow the common phonetic sound change patterns poorly. Likewise, there is a continuum between "pure" loanwords and "expressive" loanwords. The difference to a folk etymology is that a folk etymology is based on misunderstanding, whereas an expressive loan is changed on purpose, the speaker taking the loanword knowing full well that the descriptive quality is different from the original sound and meaning.
South-eastern Finnish, for example, has many expressive loans. The main source language, Russian, does not use the front rounded vowels 'y', 'ä' or 'ö' [y æ ø]. Thus, it is common to add these to redescriptivized loans to remove the degree of foreignness that the loanword would otherwise have. For example, tytinä "brawn" means "wobblyness", and superficially it looks like a native construction, originating from the verb tutista "to wobble" added with a front vowel sound in the vowel harmony. However, it is expressivized from tyyteni (which is a confusing word as -ni is a possessive suffix), which in turn is a loanword from Russian stúden' . A bit more obvious example is tökötti "sticky, tarry goo", which could be mistaken as a derivation from the onomatopoetic word tök (cf. the verb tökkiä "to poke"). However, it is an expressive loan of Russian d'ogot' "tar".
A newer example is the net slang word nyypiö, from English "newbie", which Finnish speakers would hear "njyybi". The meaning of nyypiö is distinct from "newbie" due to several reasons:
With the help of these connotations, the reader can be guided towards the correct meaning, even if he does not recognize the word "newbie" from nyypiö. Actually, one of the reasons to redescriptivize is to add a native touch to the word, preventing the mere repetition of foreign concepts.