callus (patch or hardened skin); corns (on feet); also 趼子

to make a cocoon

callus (patch or hardened skin); corns (on feet); also 老趼

silkworm cocoon

thick callus; (literary) thick silkwaste padded clothes

paper made from silkworm cocoons

lit. to break through a cocoon and turn into a butterfly (idiom); fig. to emerge strong after a period of struggle; to get to a better place after going through difficult period

to spin a cocoon around oneself (idiom); enmeshed in a trap of one's own devising; hoist by his own petard

(Internet) echo chamber; filter bubble

(lit.) to unwind the silk thread from the cocoon (idiom); (fig.) to unravel a mystery; to painstakingly follow the clues to eventually get to the bottom of the matter

to spin a cocoon around oneself (idiom); enmeshed in a trap of one's own devising; hoist with his own petard