yack /jak/noun 2forms 1phrases 1 noun2 •(dialect, no longer used) An oak.If 't ash tree buds before 't yack, […] — 1877 •(UK, no longer used) A watch (timepiece).I have got the Yacks, so do not come it. Fight cocum. — 1859 formsyacks Phrases with yack yack onTo talk at length, in an annoying, boring and long-winded way.
