1520s, "having the power or property of leading" (a sense now obsolete), from conduct (v.) + -ive. Physics sense, "resulting from or pertaining to conduction," is from 1840. Related: Conductivity (1837).
early 15c., "to guide, accompany and show the way," from Latin conductus, past participle of conducere "to lead or bring together; contribute, serve," from assimilated form of com "with, together" (see con-) + ducere "to lead" (from PIE root *deuk- "to lead").
Sense of "to lead, command, direct, manage" is from mid-15c., originally military. General meaning "to direct, manage, act as leader of" is from 1630s; especially of a musical performance (1791).
Meaning "behave in a certain way" is from 1710. In physics, "to carry, convey, transmit," 1740. Related: Conducted; conducting. An earlier verb in the same sense was condyten (c. 1400), which goes with conduit.
To conduct is to lead along, hence to attend with personal supervision; it implies the determination of the main features of administration and the securing of thoroughness in those who carry out the commands; it is used of both large things and small, but generally refers to a definite task, coming to an end or issue: as, to conduct a religious service, a funeral, a campaign. [Century Dictionary]
word-forming element making adjectives from verbs, meaning "pertaining to, tending to; doing, serving to do," in some cases from Old French -if, but usually directly from Latin adjectival suffix -ivus (source also of Italian and Spanish -ivo). In some words borrowed from French at an early date it has been reduced to -y (as in hasty, tardy).
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Definitions of conductive from WordNet
having the quality or power of conducting heat or electricity or sound; exhibiting conductivity;