n.North American cicada; appears in great numbers at infrequent intervals because the nymphs take 13 to 17 years to mature
同义词：periodical cicadaMagicicada septendecim
英汉双解大词典
seventeen-year locust
1.
N（名词）
an E North American cicada, Magicicada septendecim, appearing in great numbers at infrequent intervals because its nymphs take 13 or 17 years to mature 十七年蝉 (Also called periodical cicada)