deliberate radiation or reflection of electromagnetic energy for the purpose of disrupting enemy use of electronic devices or systems
"The drone operators had to scramble when our team launched a jamming signal that blinded their guidance systems."
A sweet mixture of fruit boiled with sugar and allowed to congeal. Often spread on bread or toast or used in jam tarts.
"After losing their bonus, the family found themselves in such deep jam that they couldn't even afford basic groceries for a week."
A kind of frock for children.
Alternative form of jamb
A household that is only barely able to meet its financial obligations.
In plain English: A jam is a situation where everything goes wrong at once and you can't move forward.
"I ate a spoonful of peanut butter jam for breakfast."
Usage: Use "jam" as a noun to describe a difficult situation or predicament where resources are insufficient to solve the problem, such as when a family struggles to pay their bills. Do not use it to refer to the fruit spread or a tight schedule unless the context clearly implies financial distress.
To get something stuck, often (though not necessarily) in a confined space.
"The old bicycle chain got jammed between the rusty gears and refused to turn."
In plain English: To jam something means to push it so hard that it gets stuck and won't move.
"The car door wouldn't open because the ice had jammed the lock."
Usage: Use "jam" to describe forcing an object into a tight space until it becomes stuck or wedged firmly in place. This applies whether you are physically shoving a door open against resistance or metaphorically getting your schedule so full that nothing else fits.
First appearing in the early 1700s as a verb meaning "to press or be wedged," jam likely originated from an imitative sound related to biting or gnashing teeth. This root eventually evolved into dialectal words for crushing food before giving rise to our modern sense of pressing things together tightly.