Antonyms of adj insecure

4 senses of insecure

Sense 1
insecure (vs. secure) -- (not firm or firmly fixed; likely to fail or give way; "the hinge is insecure")

secure (vs. insecure) -- (not likely to fail or give way; "the lock was secure"; "a secure foundation"; "a secure hold on her wrist")
        => steady -- (securely in position; not shaky; "held the ladder steady")
        => tight -- (securely or solidly fixed in place; rigid; "the bolts are tight")

Sense 2
insecure (vs. secure), unsafe -- (lacking in security or safety; "his fortune was increasingly insecure"; "an insecure future")

secure (vs. insecure) -- (free from danger or risk; "secure from harm"; "his fortune was secure"; "made a secure place for himself in his field")
        => assured -- (characterized by certainty or security; "a tiny but assured income"; "we can never have completely assured lives")
        => firm -- (securely established; "holds a firm position as the country's leading poet")
        => fail-safe -- (guaranteed not to fail; "a fail-safe recipe for cheese souffle")
        => sure -- (physically secure or dependable; "a sure footing"; "was on sure ground")

Sense 3
insecure (vs. secure) -- (lacking self-confidence or assurance; "an insecure person lacking mental stability")

secure (vs. insecure), unafraid, untroubled -- (free from fear or doubt; easy in mind; "he was secure that nothing will be held against him")

Sense 4
insecure, unsafe -- (not safe from attack)

INDIRECT (VIA vulnerable) -> invulnerable -- (immune to attack; impregnable; "gunners raked the beach from invulnerable positions on the cliffs")

Similarity of adj insecure

4 senses of insecure

Sense 1
insecure (vs. secure) -- (not firm or firmly fixed; likely to fail or give way; "the hinge is insecure")
          Also See-> unfixed#1

Sense 2
insecure (vs. secure), unsafe -- (lacking in security or safety; "his fortune was increasingly insecure"; "an insecure future")
       => precarious, shaky -- (not secure; beset with difficulties; "a shaky marriage")
       => unguaranteed, unsecured -- (without financial security; "an unsecured note")
          Also See-> dangerous#1, unsafe#2; unprotected#1; vulnerable#1

Sense 3
insecure (vs. secure) -- (lacking self-confidence or assurance; "an insecure person lacking mental stability")
       => overanxious -- (anxious or nervous to an excessive degree)
       => unassured -- (lacking boldness or confidence)

Sense 4
insecure, unsafe -- (not safe from attack)
       => vulnerable (vs. invulnerable) -- (susceptible to attack; "a vulnerable bridge")