What does "incommunicative" mean?

Incommunicative: Not communicative; not free or apt to impart to others in conversation; reserved; silent; as, the messenger was incommunicative; hence, not disposed to hold fellowship or intercourse with others; exclusive. The Chinese . . . an incommunicative nation. C. Buchanan. -- In`com*mu"ni*ca*tive*ly, adv. -- In`com*mu"ni*ca*tive*ness, n. Lamb. His usual incommunicativeness. G. Eliot.