This paper investigates the perception of emotional force of swearwords and taboo words (S-T words) among 1039 multilinguals. It is based on data drawn from a large database collected through a web questionnaire on bilingualism and emotions. "t"-Tests revealed that the perceived emotional force of S-T words is highest in the L1 and gradually lower in languages learned subsequently. Self-reported L1 attriters were found to judge S-T words in their L1 to be less powerful than those who are still dominant in their L1. Participants who learned their language(s) in a naturalistic--or partly naturalistic--context gave higher ratings on emotional force of S-T words in that language than instructed language learners. Self-rated proficiency in a language and frequency of use of language significantly predicted perception of emotional force of S-T words. Age of onset of learning was found to only predict perception of emotional force of S-T words in the L2. (Contains 3 tables, 5 figures and 2 notes.)