Akademik

поперек себя толще
• ПОПЕРЕК СЕБЯ ШИРЕ <ТОЛЩЕ> highly coll
[AdjP; these forms only; subj-compl with copula (subj: human); fixed WO]
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⇒ (to be or have become) very fat:
- X (стал) поперёк себя шире{{}}≈ X is <has grown, has become> wider than he is tall;
- X is (has become) a butterball;
- X is <has gotten to be> like the side of <as big as> a house.
     ♦ [author's usage] [Гусев:] ...У всех наших девочек вот такие дети, и все они стали шире себя... (Рощин 1). [G.:] ... All the girls I went to school with have children so high, and they've all grown wider than they're tall... (1b).

Большой русско-английский фразеологический словарь. — М.: ACT-ПРЕСС КНИГА. . 2004.