Seldom is a formal or literary word that means not often or rarely. Learn how to use it in different positions in a clause, with or without an auxiliary verb, and with synonyms and translations. Seldom definition : on only a few occasions; rarely; infrequently; not often.. See examples of SELDOM used in a sentence. SELDOM meaning : 1. almost never: 2. almost never: 3. almost never: . Learn more. The adverb ' seldom ' has its roots in Old English, specifically from the word 'seldan,' which meant 'rare' or 'infrequent.' This Old English term is related to the Middle English word 'selden' with a similar meaning . Over time, ' seldom ' evolved to become the adverb it is today, describing occurrences or events that happen rarely, infrequently, or with a low degree of regularity. The word's etymology reflects its historical association with rarity and scarcity, emphasizing the infrequent ...