What is meant by gift in contemplation of death used in section 56(2) of I TAct ?

Section 56(2)(vii) is among many exceptions provides under clause (d) that if an individual or HUF receives any sum of money without consideration (read as gift ) in contemplation of death , the receipt will not be taxable. The issue is what is the meaning of phrase “in contemplation of death ” which is not explained any where in the Income Tax Act.