Q: Is the word “disconnect” properly used as a noun?
A: Yes, “disconnect” has been a noun for more than a century, though the contemporary sense of a difference or an incompatibility is relatively new.
Webster’s New World College Dictionary (4th ed.) considers the newer sense informal, but the other six standard dictionaries we’ve checked list it without comment, indicating that it’s used in formal as well as informal English.
Although the noun “disconnect” is a relative newcomer (it dates from the early 1900s), “disconnection” has been a noun since the mid-1600s, meaning lack of connection, separation, or detachment.
The earliest example for “disconnection” in the Oxford English Dictionary is from Jasper Mayne’s 1663 translation of Lucian’s Dialogues:
“He still raises the derision of the auditory by his disconnections, and tautologies, and Nonplusses.”
The shorter word “disconnect” first showed up in English in the mid-1700s as a verb meaning to destroy the logical connection between things or to cause things to become disjointed.
The verb ultimately comes from Latin: the prefix –dis (apart) and the verb conectere (to join together).
The earliest example in the OED is from Moravian Heresy, a 1751 treatise by John Roche denouncing the Moravian Church:
“And if the Text does not chance to have Words enough sufficient to make a full Answer to the Question put, then the Sense is defective; if too many Words, then do they disconnect the Tenor, and confound the Sense.” (We’ve expanded the citation.)
Over the years, according to OED citations, the verb took on many related senses, including to break a physical connection (1758), to detach an electrical device from its power supply (1826), to end a telephone call (1877), to withdraw from society or reality (1961), and to terminate a computer connection (1977).
When the noun showed up in the early 20th century, the dictionary says, it referred to an “act or instance of disconnecting something; esp. a break of an electrical or telephone connection.”
The OED’s earliest example of the noun is from Telephony, a 1905 book by A. V. Abbott about the design, construction, and operation of telephone exchanges: “These signals must appear as a disconnect as soon as the receivers are replaced.”
The noun took on its contemporary sense of “a lack of consistency, understanding or agreement; a discrepancy” in the early 1980s, according to Oxford.
The dictionary’s earliest example is from a 1982 issue of Parameters, a journal of the US Army War College: “The result was the same: a disconnect between the security policy and the military strategy needed to achieve the political objective.”