An Etymological Dictionary of the German Language/Annotated/blasen
blasen, verb, ‘to blow, sound, smelt,’ from Middle High German blâsen, Old High German blâsan, ‘to breathe, snort’; compare tho equivalent Gothic blêsan; in English only the derivative Anglo-Saxon blœst, English blast, has been preserved. The s of blasen, which does not occur in the root bhlê of the cognate languages, is considered by some to be simply a present suffix which was not joined to the stem until a later period; in that case blähen and Blatter may be cognate. The Old Teutonic words with initial bl separate into two groups; the one, containing blähen, Blatter, blasen, blühen, Blüte, seems to be based on the primary meaning of ‘swelling,’ the other, comprising blank, blaß, blinken, blecken, blißen, blau, Blech, Blut, on the notion of ‘shining.’