Accumulating knowledge and experience across the lifespan are bound to have an impact on the meaning of words. Here, we investigated this idea using primarily emotional valence of words as a test-case. We used French databases that gather psycholinguistic variables including emotional valence of words, in four groups of individuals including young (18-25; 26-39 years), middle-aged (40-59 years) and older (>60 years) adults. Following the hypothesis that words may display age-related differences in their psycholinguistic properties, we computed linear regressions over all individual words as a function of age-groups. Results revealed notably that between 5 and 10% of words show significant linear changes of emotional valence as a function of age. This pattern highlights the situated and flexible nature of word meanings and suggests that self-relevance of experience affects semantic memory.