Senses
没要紧/ 沒要緊 not serious
not serious or life-threatening (usually of an illness or injury)
没要紧/ 沒要緊 muddle-headed
confused or muddle-headed; specifically used in literary contexts to describe someone who lacks focus or sense
没要紧/ 沒要緊 unimportant
not important; of no consequence; (conversational) it doesn't matter