1.To crouch or squat; to sit on one's haunches.
2.To settle in at a location for an extended period; also (figuratively) to maintain a position and resist yielding to some pressure, as of public opinion.
3.To take shelter, literally or figuratively; to assume a defensive position to resist difficulties. "We hunkered down to ride out the storm in an abandoned cabin." "While many businessmen were hunkering down for another bust after the lean years of the Second World War and the Great Depression before it, Taylor and company correctly reckoned it was the dawn of an era of prosperity and growth."
