Real Dictionary

I'll
I'll is the usual spoken form of 'I will' or 'I shall'.

I'll in American English
contraction of: I will

I'll in British English
contraction of: I will or I shall

ill
Someone who is ill is suffering from a disease or a health problem.

Ill in American English
Illinois
adjective: of unsound physical or mental health; unwell; sick

ill in American English 1
characterized by, causing, or tending to cause harm or evil

ill in American English 2
illustrated

ill in British English
adjective: not in good health; sick

ill-
combining form: Ill- is added to words, especially adjectives and past participles, to add the meaning 'badly' or 'inadequately'. For example, 'ill-written' means badly written.

ill. in American English
abbreviation: Illinois
abbreviation: illustrated

Ill. in British English
abbreviation for: Illinois