If someone loosens restrictions or laws, for example, they make them less strict or severe.

If someone or something loosens the ties between people or groups of people, or if the ties loosen, they become weaker.

If you loosen your clothing or something that is tied or fastened or if it loosens, you undo it slightly so that it is less tight or less firmly held in place.

If you loosen something that is stretched across something else, you make it less stretched or tight.

If you loosen your grip on something, or if your grip loosens, you hold it less tightly.

If a government or organization loosens its grip on a group of people or an activity, or if its grip loosens, it begins to have less control over it.

If you say that something has loosened someone's tongue, you mean that it has made them talk about something, often when they should have remained silent.