As a pronoun:
* "that one" or "the one": This is the most common meaning of "celui" when used as a pronoun. For example, "J'aime celui-ci." (I like that one.)
* "he" or "him": This is less common but possible, especially in older French or formal writing. For example, "Celui qui a volé le pain est parti." (The one who stole the bread has left.)
As part of a compound word:
* "celui-ci" = "this one": This indicates something near the speaker.
* "celui-là" = "that one": This indicates something further away from the speaker.
It's important to note that "celui" is often used in conjunction with other words to create phrases with specific meanings. For example:
* "celui de" = "the one of": This refers to something that belongs to someone.
* "celui qui" = "the one who" or "he who": This introduces a relative clause.
Ultimately, the best way to understand the meaning of "celui" is to look at the entire sentence and the context it's used in.