The phrase "an undefined period" is correct and usable in written English.
It can be used when referring to a time frame that has not been specified or determined.
Example: "The project will be on hold for an undefined period until we receive further instructions."
Alternatives: "an indeterminate duration" or "an unspecified time frame".
The U.S. plan is to leave as many as 40,000 troops to continue to assist Iraq in training, logistics and intelligence for an undefined period.
"Without any explanation or accountability, Yahoo has been left to flounder under a discredited leader for an undefined period," Mr. Loeb wrote.
Each tracks a spatially and emotionally ambiguous scene, as well as an undefined period of time, using a high definition camera that moves almost continuously across a lavishly detailed set.
The request by the Palestinians to be admitted to the United Nations as a full member state, formally submitted on Friday, will now be considered by the security council for an undefined period, during which efforts to get both sides back to the negotiating table will intensify.
Between each succession actions, the individuals were supposed to return to a resting state for an undefined period.
As part of this effort, we are testing trends clearly marked as "promoted" for an undefined period of time," a Twitter representative tells us.
This level of diversity between sheep isolates suggests that mecC-MRSA ST130 may have been circulating in the flock for an extended undefined period of time, or had been introduced into the flock on at least two occasions prior to the human infection in order to allow this number of SNPs to accumulate.
But this would be only in the framework of a non-belligerence agreement for a long and undefined period of time".
This tenure arrangement is valid as long as the deposit is not repaid Loan (temporary borrowing) The land is loaned for a temporary or undefined period, without any security deposit or monetary transaction.
It retained the right to revisit the issue and gave lawmakers an undefined "reasonable period of time" to forge a solution.
Putin's late-stage intervention into the crisis could bring about a resolution that, rather ironically, was on offer long ago: Assad in power, for an undefined transitional period, with his regime backed by Russia and Iran.
