<div>Regarding tight clothing, I think the best source is "Mah Yarech Baseser" (based on "Chamukei Yerechayich"). Baseser does not mean merely "covered", but "concealed/hidden from view". If I wanted to hide money I would not allow its outline to be clearly visible underneath its covering - that's not hidden.</div>
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<div>[ That's as far as the Yarech, though. There are somewhat more lenient standards for the torso (based on the description of the Badim as protruding from the Paroches K'shnei Dadei Ishah (Gemara Menachos and Rashi to Yoma)), and there is no prohibition on clothing which follow the contours of the arms. ]</div>