Here's a breakdown:
* Uni means one.
* Lateral refers to a side.
Therefore, unilateral actions or decisions involve only one party or entity, without the input or agreement of others.
Examples:
* Unilateral declaration of war: One country declaring war on another without any prior negotiations or agreements.
* Unilateral trade sanctions: One country imposing trade restrictions on another without any mutual agreement.
* Unilateral decision to leave a treaty: One country deciding to withdraw from an international agreement without consulting or obtaining consent from other signatories.
Contrast with "Bilateral"
Bilateral means involving two sides, so a bilateral agreement is one made between two parties.
In summary:
* Unilateral = One side
* Bilateral = Two sides