‘危急’ is an adjective meaning 'critical' or 'dire', describing a situation that is extremely dangerous or urgent, often with serious consequences if not addressed immediately. The first character 危 (wēi) means 'dangerous' or 'perilous', while the second character 急 (jí) means 'urgent' or 'immediate'. Together, they intensify each other—neither character stands alone in this compound; it functions as a fixed two-character adjective emphasizing both severity and time-sensitivity.

This word is commonly used in formal, written, or professional contexts—especially in news reports, medical settings, disaster response, and official announcements. It’s rarely used in casual daily speech; native speakers tend to say 紧急 (jǐn jí) for general urgency or 危险 (wēi xiǎn) for simple danger. ‘危急’ implies a high-stakes, deteriorating condition requiring immediate action, such as life-threatening health crises or large-scale emergencies.