The word for clover (Trifolium) in both Scots Gaelic and Irish is seamair.
In both languages shamrock is considered to be a small or young clover. So, in Irish it is:
seamair + óg = seamróg
The English word shamrock is an approximate pronunciation of seamróg.
In Scots Gaelic the word for young is òg (the doofer goes the other way 😃 ).