随时随刻 is an adverbial phrase meaning 'at any moment' or 'instantly', emphasizing immediacy and constant readiness. Literally, it repeats 随 (‘to follow’ or ‘according to’) with two time-related nouns: 时 (‘time’, often referring to broader timeframes like hours or occasions) and 刻 (‘moment’, a more precise, fleeting unit — historically one of 96 divisions of a day). The reduplication (随 + 时 + 随 + 刻) strengthens the sense of uninterrupted availability or responsiveness across all temporal scales.

This phrase is commonly used in formal or semi-formal contexts — such as customer service promises, emergency protocols, or digital platform features — to convey unwavering accessibility. It’s more emphatic and slightly more literary than simpler alternatives like 随时 or 随地, and it carries a tone of reliability and urgency. While grammatically flexible, it most frequently modifies verbs indicating action, response, or availability (e.g., 联系, 响应, 准备).