Synonyms of high-priority

1 Syllable
crying, dire
2 Syllables
pressing, clamant, burning, claiming, heat-on, serious, heaton, instant, forcing, vital, crucial
3 Syllables
demanding, insistent, critical, distressing, requiring, hurry-up, life-and-death, constraining, acute, compelling, clamorous, exigent, obliging, exacting
4 Syllables
immediate
5 Syllables
importunate, imperative