What does "groan" mean?

Additional senses

1. 2.To strive after earnestly, as with groans. Nothing but holy, pure, and clear, Or that which groaneth to be so. Herbert.
2. 3.To affect by groans.
3. 4.A low, moaning sound; usually, a deep, mournful sound uttered in pain or great distress; sometimes, an expression of strong disapprobation; as, the remark was received with groans. Such groans of roaring wind and rain. Shak. The wretched animal heaved forth such groans. Shak.