The tip-of-the-tongue (TOT) phenomenon, the inability to immediately retrie
ve a word one desires, was studied in bilingual Farsi-English-speaking adul
ts. One question was whether insufficient activation or increased inhibitio
n underlie TOT states in bilinguals. Another was whether bilinguals have co
mmon or separate lexicons for their two languages. Participants heard a def
inition in either Farsi or English followed by either a Farsi or English pr
ime word related in meaning or sound, or nor at all related, to the target
word. Participants supplied the target word that best fit the definition. S
imilar-sound primes increased TOTs for English definitions and targets, wit
h a trend for more correct responses as well, suggesting that the similar-s
ound prime word facilitates rather than inhibits retrieval, supporting the
transmission deficit hypothesis. Primes had the same effect for same and di
fferent language conditions, suggesting that both Farsi and English map ont
o a single lexicon, supporting the single-store model of bilingual memory.