topmost layer
nounUK /ˈtɒp.məʊst ˈleɪ.ə/
US /ˈtɑːp.moʊst ˈleɪ.ɚ/
The topmost layer is the very top part of something.
The topmost layer of the cake is covered in chocolate frosting.
OTHER MEANINGS
2. The highest level or rank in a group or system.
Only the topmost layer of management attended the meeting.
3. The most visible or apparent part of something complex.
The report only examined the topmost layer of the problem.
4. The final coat applied to a surface, such as paint or varnish.
The topmost layer of paint gives the wall its glossy finish.