off-hook

(redirected from Off hook)
Also found in: Acronyms.

off-hook

[′ȯf ‚hu̇k]
(communications)
The active state (closed loop) of a subscriber or PBX user loop.

off-hook

The state of a telephone line that allows dialing and transmission but prohibits incoming calls from being answered. The phone is off-hook when the handset is lifted off the base of a stationary phone or when Talk is pressed on a portable phone.

The term stems from the days when the handset rested on an actual hook. When it was removed, a spring caused contacts to press together, closing the circuit from the telephone to the switchboard in the central office (CO). When a handset is placed back on the base, it is said to be "on-hook," and the phone can receive a call. See central office.


There Really Was a Hook
The hook on this Kellogg telephone (circa 1899) was attached to a spring. When the handset was removed, the contacts inside completed the circuit between the telephone and the central office.
References in periodicals archive ?
HEAT'S EAT'SEA OFFDaly nets the opener then Black blasts his free-kick and celebrates the goal, above, that gets Foster, below, off hook with fans HEAT'S EAT'SEA OFFDaly
Explaining why he had made the bold move of taking off Hook and Phillips with Saturday's game in the balance at 17-15, Gatland said it had been a time for old heads.
Ann Cott, sister of Maggie B skipper Glen Cott, and Fr Peadar O'Callaghan arrive to say prayers at the raised trawler; BEFORE The Maggie B before and after the trawler sank claiming the lives of two crewmen; BEFORE Five men died when the trawler Pere Charles Trawler went down last January off Hook Head.
D'Arcy burst for the line and was stopped inches short but O'Gara, after such a disappointing first 70 minutes, picked up the recycled ball and held off Hook's tackle to touch down in the corner.
In most call centers, agents work "off hook" with headsets.
If he does put boot to ball, then it would take some of the pressure off Hook, who is still going through a learning process when it comes to tactical kicking.
The stricken Maggie B sank off the coast of Co Wexford about 8km south off Hook Head, March last year.
Rescue workers were already involved in a massive search operation for five men after the Pere Charles sank in seconds off Hook Head, Co Waterford, on Wednesday night.
The bodies of skipper Tom Hennessy, 32, uncle Pat Hennessy, 48, Billy O'Connor, 50, Pat Coady, 27, and 32-year-old Andriy Dyrin have not been recovered since the Pere Charles sank about four kilometres off Hook Head on January 10th.
Take telephone off hook. Purse out with contents spread about."
6, at the Round Lake Beach Cultural & Civic Center, located off Hook Drive west of Route 83.