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general::
Phrase(s): at the bottom of the ladder [and] on the bottom rung (of the ladder)
Fig. at the lowest level of pay and status. (Alludes to the lowness of the bottom rung of a ladder.) • Most people start work at the bottom of the ladder. • After Ann got fired, she had to start all over again on the bottom rung.
McGrawhill's American Idioms And Phrasal Verbs