| Blue | a coarse prickly European weed with spikes of blue flowers |
|---|---|
| Blue | a fit of despondency |
| Blue | acute delirium caused by alcohol poisoning |
| Blue | shrub or small tree of western United States having white flowers and blue berries |
| Blue | shrub or small tree of western United States having white flowers and blue berries |
| Blue | wild indigo of the eastern United States having racemes of blue flowers |
| Blue | Australian tree having hard white timber and glossy green leaves with white flowers followed by one-seeded glossy blue fruit |
| Blue | the fruit of the Brisbane quandong tree |
| Blue | a common iris of the eastern United States having blue or blue-violet flowers |
| Blue | widespread weed with pale purple-blue flowers |
| Blue | a variety of arctic fox having a pale gray winter coat |
| Blue | a state of nervous depression |