WordNet sense 1 (of momentous or ominous significance):

portentous

WordNet sense 2 (worthy of notice):

noteworthy

WordNet sense 3 (of very great significance):

momentous

WordNet sense 4 (important in effect or meaning):

important

WordNet sense 5 (rich in significance or implication):

meaning, pregnant

WordNet sense 6 (having a meaning or purpose):

meaningful

WordNet sense 7 (fairly large):

substantial

WordNet sense 8 (large or relatively large in number or amount or extent or degree):

considerable