Webster's Revised Unabridged Dictionary · 1913

Eruptive

Eruptive , adjective

[Compare French éruptif.]

1.
Breaking out or bursting forth.
The sudden glance Appears far south eruptive through the cloud. — Thomson
2.
(Medicine) Attended with eruption or efflorescence, or producing it; as, an eruptive fever.
3.
(Geology) Produced by eruption; as, eruptive rocks, such as the igneous or volcanic.

Eruptive , noun

(Geology) An eruptive rock.