Answer:

meniscus

AnswerCrossword Clue
MENISCUSKnee cartilage
MENISCUSCrescent-shaped part of a lens
MENISCUSCrescent-shaped thing.
MENISCUSCrescent
MENISCUSLens with a crescent-shaped section
MENISCUSCrescent-shaped section of a lens
MENISCUSConcavo-convex lens
MENISCUSFull-glass phenomenon