n.one of a series of rounded projections (or the notches between them) formed by curves along an edge (as the edge of a leaf or piece of cloth or the margin of a shell or a shriveled red blood cell observed in a hypertonic solution etc.)
同义词：scallopcrenaturecrenelcrenelle
英汉双解大词典
crenation/ˈkrɛnəˌtjʊə, ˈkriː-/(alsocrenature)
1.
N（名词）
any of the rounded teeth or the notches between them on a crenate structure 圆锯齿