at bottom
Basically; ultimately. I know John can be annoying, but at bottom he's a good person.
at bottom
Fundamentally, basically; also, in reality. For example, He may speak somewhat bluntly, but at bottom he's always honest. Charles Dickens used this idiom in Nicholas Nickleby (1838): "He's a good pony at bottom." [Early 1700s]
at ˈbottom
basically; in reality: She seems rather unfriendly, but at bottom I think she’s quite kind.