Some may consider short term life insurance to be any life insurance plan that lasts for 20 years or less. Whereas, a long term life insurance policy may be one that lasts for 30 years or more, depending on your long term needs.
There are term life insurance plans that provide long term coverage of up to 30 years with level rates that are guaranteed to remain the same for the 30 year term.
In addition, there are permanent life insurance policies which provide lifetime coverage.
The difference being that permanent life insurance costs a lot more than term, and it may build up cash value inside the life insurance policy over time.
Term life is pure life insurance protection, not an investment, and offers the lowest rates for up to 30 years.
Also, term life may offer an option of renewability where you could renew your term life policy for 10 years when the term life insurance expires, without having to take a physical exam to qualify for the renewal. But, your new life insurance rate for the renewal policy will be based on your age at that time.