recap: [20] The -cap of recap has of course no immediate connection with cap. The word is short for recapitulate [16], which etymologically denotes ‘repeat the headings’. It comes from late Latin recapitulāre, a compound verb formed from the prefix re- ‘again’ and capitulum ‘section of text, heading’ (source of English chapter). Capitulum was a diminutive form of Latin caput ‘head’, which may ultimately underlie English cap – so the two words could after all be linked. => capitulate, chapter[recap etymology, recap origin, 英语词源]