Esker and Hummocks

Esker noun - (geology) a long winding ridge of post glacial gravel and other sediment; deposited by meltwater from glaciers or ice sheets.

Hummocks and esker are semantically related In some cases you can replace term "Hummocks" with "Esker", this nouns are similar.

Esker and hummocks are semantically related in pile topic. Sometimes you can use "Esker" instead a noun "Hummocks", if it concerns topics such as small hill.