Noun:

1. drooping of the upper eyelid caused by muscle paralysis and weakness

PTOabbr.见反面(=please turn over)abbr.动力起飞(=power takeoff)abbr.家长教师联谊组织(=parent-teacher organization)pto clutch lever动力输出轴离合器操纵杆ptosis acquisita后天性上睑下垂PTolemaic systemn.[天]托勒密之天动学说Ptosis of eyelid上睑下垂ptosis congenita先天性上睑下垂ptosis of kidney[医] 肾下垂ptosis atrophica萎缩性上睑下垂, 睑皮松弛(症)ptosis operation上睑下垂手术ptomaine-domainn.专门用餐的地方；食堂；自助餐厅Ptolemaic theorem托勒米定理

false ptosis脂肪性上睑下垂, 假性上睑下垂

abdominal ptosis[医] [腹]内脏下垂

congenital ptosis先天性上睑下垂