Approach 1: using DENSE_RANK()
Below example is for getting third largest salary.
Consider following details :
Table: Emp
Column: name, Salary
(SELECT name , salary , DENSE_RANK() over (order by salary desc) AS Rowno FROM emp) a
Where a.Rowno=3
Approach 2: using subquery
SELECT MIN(Salary) from EMP where salary in
(SELECT TOP 3 salary from emp e order by salary desc)