Technicism is an over reliance or overconfidence in technology as a benefactor of society.
Taken to the extreme, some argue that technicism is the belief that humanity will ultimately be able to control the entirety of existence using technology. In other words, human beings will eventually be able to master all problems, supply all wants and needs, possibly even control the future. (For a more complete treatment of the topic, see the work of Egbert Schuurman, for example at.1) Some, such as Monsma, et al., connect these ideas to the abdication of religion as a higher moral authority.
More commonly, technicism is a criticism of the commonly held belief that newer, more recently developed technology is "better." For example, more recently developed computers are faster than older computers, and more recently developed cars have greater gas efficiency and more features than older cars. Because current technologies are generally accepted as good, future technological developments are not considered circumspectly, resulting in what seems to be a blind acceptance of technological developments.