The word 一阵子 is formed by combining the numeral 一 (meaning "one" or "a"), the character 阵 (which serves as a measure word denoting a short period or spell of time), and the suffix 子 (which nominalizes the construction and imparts a casual, colloquial quality). Together, these characters directly create a phrase meaning "a while" or "a short period", with each element contributing to this specific temporal expression.