1. Accept and Except
These words are sometimes confused, but can have opposite meanings depending on the context. To accept means to receive something willingly, whereas to except something means to leave it out.
2. Aisle and Isle
An aisle is a walkway between sections, as in a theater or plane. An isle is a small island. To further confuse matters, both sound like the contraction of I and will: I’ll.
3. Appraise and Apprise
To appraise means to estimate the value of or assess. To apprise means to inform. As in, he was apprised of the house appraisal before making an offer.
4. Assent and Ascent
These words have the same pronunciation but quite different meanings. Assent means agreement and is also a verb. Ascent means climb.
5. Allusion and Illusion
An allusion is a reference; an illusion is something imagined or deceptive.