hummock

山で遭難した９歳の少女Trishaの山歩きは続きます。
Ahead (and already around her) was a broken maze of long-dead trees. The ground in which they stood was swampy and wet. Rising from flat pools of standing water were turtleback hummocks covered with grass and swatches of weeds. The air hummed with mosquitoes and danced with dragonflies.
"hummock" は日本語になっているハンモックとは明らかに違いますね。辞書を見ます。
・Collins Dictionary: a wooded area lying above the level of an adjacent marsh: She half-stumbled over a hummock of grass as she rushed towards her mother.
・Vocabulary.com: You don't swing in a hummock, you climb one. A hummock is a hill, a mound, or a ridge.
This word was once a nautical term describing a hill rising up on a coastline. A hummock is a perfect place for a lighthouse. Today it is either a rounded hill or an elevated place in an ice field. The origin of the word is unknown, but the ending -ock is a diminutive, meaning it gives the noun the sense of being small. That is why a hummock is a knoll and not a mountain.
日本語になっているハンモックのスペルは "hammock" でした。スペルが違う様に発音も違います。