hardheads

noun

1. 1

   One who is practical or hardheaded.

2. 2

   A brown diving duck, Aythya australis, native to Australia.

3. 3

   Any of various freshwater cyprinid fishes of the genus Mylopharodon, or of saltwater sciaenid (Sciaenidae) fishes.

4. 4

   Any of several weeds in or formerly classified in the genus Centaurea, particularly Russian knapweed (Acroptilon repens).

5. 5

   Residual ore that failed to melt during a smelting process.

6. 6

   Clash or collision of heads in contest.

7. 7

   A Scottish billon coin circulated in the reigns of Mary and James VI.