### Clue: English thorns; hoary symbols, primarily? (4)
### Answer: ETHS 
 ### Explanation: Definition: English thorns; hoary symbols, primarily
First letters ('primarily') of '**E**nglish **T**horns **H**oary **S**ymbols'. In Old English letters ð eth and Þ thorn were used interchangeably for voiced or unvoiced th.