菸 (yān) is a bound form (b.f.) that appears in compounds related to tobacco or cigarettes. It is a variant of the more common character 烟 (yān), though in modern usage 烟 is preferred for most contexts. You will see 菸 in formal or literary compounds like 菸草 (tobacco) and 菸民 (smoker). The gloss 'withered/dry leaves' is an obscure or historical sense; the practical function of this character is as a written variant for tobacco-related terms.