UNHCR:  Article 1A(2) of the 1951 Convention defines a refugee any person who:
“As a result of events occurring before 1 January 1951 and owing to well-founded fear of being persecuted for reasons of race, religion, nationality, membership of a particular social group or political opinion, is outside the country of his [or her] nationality and is unable, or owing to such fear, is unwilling to avail him [or her]self of the protection of that country; or who, not having a nationality and being outside the country of his [or her] former habitual residence as a result of such events, is unable or, owing to such fear, is unwilling to return to it.” 

An immigrant is different. The main similarity is that both the immigrant and refugee comes from another country different from their current locations. However, immigration is planned and not abrupt. The motivation is for taking up employment either temporarily or permanently, or establishing habitat within a chosen foreign country.
(Wikipedia The Free Encyclopedia, 2016)

An asylee is an immigrant. However, like refugees, the asylee uses evidence of past persecution and fear, to find protection and regularize their residence in their new country. The asylee however, like the immigrant, travels in a planned and prepared manner, and not abruptly like the refugee.
(Immigration Equality, 2016).