The present study examined within – and cross-language priming patterns among German-English-French trilinguals in order to explore the lexico-semantic representation of L3 in relation to L1 and L2. The trilinguals participated in three lexical decision tasks within the masked translation priming paradigm. The results showed significant within-language repetition priming effects in all three languages, significant translation priming effects for L2-L1, L1-L3, and L2-L3, but no significant priming for L1-L2, L3-L1 or L3-L2. Our findings demonstrate that translation priming asymmetry persists in trilinguals and that the weakest L3 is integrated into both L1 and L2 conceptually (i.e. three languages have a commonly shared conceptual representation). In addition, our results showed a language dominance shift over lexical development between L1 and L2. We argue for a modified Sense Model as the best fit to explain the cognitive architecture of the trilingual lexicon. [ABSTRACT FROM AUTHOR]