Resilience is a deeply rooted word in theory of elasticity, which is firstly introduced to English by Thomas Young in 1807 in his treatise “A course of lectures on natural philosophy and the mechanical arts”. However, recently it is frequently used in ecology, economics, social sciences, and as everyone knows in the disaster literature. The purpose of this article is to investigate the mechanical background of word resilience, discuss lessons we could learn from the theory of elasticity for evaluating tsunami resilience, and finally, to propose a new mathematical model based on theory of springs. The mathematical model is in compliance with a pragmatic conceptual framework for evaluating resilience. The effective resilience of a given area can be calculated by aggregation of three components namely, onsite capacity, instantaneous survivability, and recovery potential of the area. The authors suggest that the magnitude of each component depends on socioeconomic, infrastructural and geographical factors of the area considered. Here, we show that aggregation of the individual components can be done in compliance with the theory of springs by analogizing effective tsunami resilience to effective spring constant. The mathematical model will be useful for evaluating the resilience of townships to hydrological disasters and also planning resilient townships, specifically to tsunami.