THESAURUS
critical point
bench mark, cardinal point, chief thing, climacteric, climax, clutch, convergence of events, core, cornerstone, crisis, critical juncture, crossroads, crucial period, crunch, crux, emergency, essence, essential, essential matter, exigency, extremity, fundamental, gist, gravamen, great point, heart, high point, hinge, important thing, issue, kernel, keystone, landmark, main point, main thing, material point, meat, milestone, nub, pass, pinch, pith, pivot, push, real issue, rub, salient point, sine qua non, strait, substance, substantive point, the bottom line, the point, turn, turning point