Meaning of ALTHOUGH in English
1》 in spite of the fact that.
2》 however; but.
Although can often be replaced by though , the only difference being that ~ is slightly more formal. Some uses are not interchangeable, however: e.g. adverbial uses ( it was nice of him to phone, though ) and uses in phrases with ‘as’ or ‘even’ ( she doesn't look as though she's listening ).
Concise Oxford English vocab. Сжатый оксфордский словарь английского языка. 2004