* Adjective: This is the most common use of "lesser." It describes a noun as being smaller or less important than something else.
* Example: "The lesser of the two evils."
* Comparative Adjective: It can also be a comparative adjective, meaning it shows a difference in degree between two things.
* Example: "The lesser known brother."
* Noun: While less common, "lesser" can be used as a noun to refer to something that is smaller or less important.
* Example: "He was not considered a lesser in the group."
So, the part of speech depends on the context!