Learner's definition of PECULIAR
[more peculiar; most peculiar]
1 : not usual or normal
It seems peculiar that he would leave town and not tell anybody.
The dog's peculiar behavior worried them.
She got a peculiar feeling when the phone rang.
She had a peculiar expression on her face.
2 not used before a noun, British, informal : not well: somewhat ill
: of, relating to, or found in (only one person, thing, or place)