significance implies a quality or character that should mark a thing as important but that is not self-evident and may or may not be recognized.

The significance of something is the importance that it has, usually because it will have an effect on a situation or shows something about a situation.

The discovery of the new drug is of great significance for/to people suffering from heart problems.

1. The state or quality of being significant: a matter of some significance. See Synonyms at importance. 2. A meaning that is expressed or implied: What was the significance of that smile?

significance, n. meanings, etymology, pronunciation and more in the Oxford English Dictionary

sig•nif•i•cance (sig nif′ i kəns), n. importance; consequence: the significance of the new treaty. meaning; import: The familiar place had a new significance for her. the quality of being significant …

An item's significance is a sign of its importance. The significance of something can be implicit or explicit — meaning it can be clear or only known with a deeper understanding of the situation.