The word 赶紧 is formed through the semantic combination of its two constituent characters: 赶, which carries the core meaning of "to rush" or "to hurry up", and 紧, which means "tight", "urgent", or "tense". Their fusion is not merely additive but conceptually multiplicative; the sense of "tight" or "under pressure" from 紧 intensifies and modifies the action of "rushing" in 赶, resulting in a compounded meaning that conveys an immediate, urgent haste, as if compelled by tightening circumstances. This creates a single, unified concept of acting swiftly and without delay.