As accented here, the headword should be the present indicative active, first person singular, of fusa/w ('blow'), for which the first gloss (breathe) is perfectly appropriate; however, the second gloss and the quotation from Aristophanes that follows suggest that the word is being conflated with the verb fu/w ('make grow') and/or its future fu/sw.
[1] Aristophanes, Birds 765, with fa/tores (conjecturally, 'speakers'), unattested outside the Suda, in place of Aristophanes' fra/teres ('phratry-members'). The same passage is quoted more accurately at kappa 352, but the spurious fa/tores shows up again at phi 135 in material probably drawn from this entry. The quotation contains the aorist imperative, third person singular, of fu/w, which the lexicographer may be conflating with the corresponding present imperative of fusa/w.