hunker down (Verb) — Sit on one's heels. ex. "The children hunkered down to protect themselves from the sandstorm"
hunker down (Verb) — Take shelter. ex. "During the sandstorm, they hunkered down in a small hut"
hunker down (Verb) — Hold stubbornly to a position. ex. "The wife hunkered down and the husband's resistance began to break down"
hunker down (Verb) — Get to work and focus on a task.