Conversation so far:
what is another name for a three leaf clover
Shamrock usually refers to either the species Trifolium dubium (lesser clover), or Trifolium repens (white clover).
where does the word shamrock come from
The name shamrock comes from Irish seamróg, which is the diminutive of the Irish word seamair óg and simply means young clover.

Question: is it only used for clover
Self-contained rewrite: is the word shamrock only used for clover