(oil industry) A method to shut off a faulty blowout preventer (BOP) by injecting the BOP with material that will clog up the innards and result in a choking off of the hole.

(UK, US, informal) A worthless or malfunctioning piece of mechanical or electrical equipment.

plural of junk science

(uncountable, derogatory) Assertions that have the appearance, but not the actuality, of scientific support.

(informal) Food with little or no nutritional value.

(genetics) Any portion of the DNA sequence of a chromosome or a genome with no apparent function.

Any mail or letters that are not welcome or solicited and typically sent in bulk; especially mail of a commercial nature such as advertising circulars and form letters.

(finance) A bond (an instrument of debt) which is considered below "investment grade" due to a significant risk of default by the issuer. The interest rate is higher in order to compensate holders for that risk.

(informal) Space debris.

(slang) Experiencing the nausea sometimes suffered by the user of a narcotic the following day, or after the effects of the drug begin to wear off, often with flulike symptoms.