Meaning of LOWER in English
[adjective] [not gradable] - positioned below one or more similar things, or of the bottom part of somethingHer lower lip trembled as if she was about to cry.Our cabin on the ship was on one of the lower decks.I've got a pain in my lower (= the bottom part of my) back, doctor.Letters that are printed or written in lower case are in the small form, not in capital letters.Please change all capitals to lower-case letters. Compare upper case at upper (HIGHER).Lower class means of the people who belong to the class that has the lowest position in society and the least money. The lower classes are these people considered as a group.a lower class workerlower class attitudesThe lower classes usually have the lowest paid jobs. Compare upper class at upper (HIGHER); middle class at middle; working class at work (ACTIVITY).The lower house is one of the two parts of a country's government that makes laws, usually the one with the most power.
Cambridge English vocab. Кембриджский английский словарь. 2012