尖部 is read as せんぶ (sembu) and means apex.
せんぶ
sembu
はいせんぶ
pulmonary apex region
とがる
to taper to a point
かんぶ
management
いちぶ
one copy (e.g. of a document)
ほんぶ
headquarters
ないぶ
interior
がくぶ
department of a university
ぜんぶ
all
ほくぶ
northern part
とうぶ
eastern part
がいぶ
outside (e.g. of a building)
なんぶ
southern part