About UK refugees and asylum seekers: Simple Definitions
Asylum Seeker: someone who has claimed asylum in a country that has signed up to the 1951 UN Convention on Refugees and is awaiting a decision. (The UK is a signatory, as are the vast majority of UN member states.)
Refugee: someone whose asylum claim has been accepted and has been granted leave to remain in the country.
‘Failed’ (or refused) asylum seeker: someone whose claim has been rejected. They have no recourse to public funds and are liable to be removed from the country.
Migrant: someone who has moved from one place to another, usually another country. That may be for any reason, often work or ‘a better life’.
Economic migrant: someone who has moved for work purposes. They may be legally here as an EU citizen or a non-EU citizen on a work visa, or here working illegally with no permit – see ‘Illegal immigrant’ below.
Illegal immigrant: someone who is here with no visa granting the right to stay and who has not sought asylum, or someone who has overstayed their visa or gone underground after their asylum claim is refused.
You can find more comprehensive definitions on the Refugee Council or the Amnesty International websites.