Meaning of AT HOME in English

AT HOME

I. noun

Date: 1745

: a reception given at one's home

II. phrasal

1. : relaxed and comfortable : at ease

felt completely at home on the stage

2. : in harmony with the surroundings

3. : on familiar ground : knowledgeable

teachers at home in their subject fields

Merriam-Webster's Collegiate English vocabulary.      Энциклопедический словарь английского языка Merriam Webster.