а. понимать; Would you mind repeating that, I didn't quite latch. б. присоединяться к кому-л. без приглашения; The party of climbers was all organized when this other man latched on and demanded to come with us.
LATCH ON
Англо-русский перевод LATCH ON
Мюллер. English-Russian Muller's dictionary bed edition. Англо-Русский словарь Мюллера редакция bed. 2012