There is no sole significance meaning for laurel. Laurel nobilis of southern Europe was used by the ancient Greeks to crown victors in the Pythian games, but the 19th century books on flower meanings were varied in interpretation, depending on what was called laurel. 19th century lists of meanings have these for laurel:
Laurel nobilis:
1883- glory; 1885-1892- glory.
American Laurel:
1883- words, though sweet, may deceive.
Common laurel:
1885-1892- perfidy.
Ground laurel:
1885-1892- perseverance.
Mountain laurel:
1883- Glory, ambition; 1885-1892- Ambition, dignity; 1899- ambition, hero.
Laurel-leaved magnolia:
1885-1892- dignity.

See: Flower Language