Language-related uncertainties occur when people, such as monolingual English speakers, encounter ambiguous words with multiple meanings, such as the word “bank” which could refer to the edge of land near a body of water or a financial institution. However, such uncertainties are greater for bilinguals or multilinguals because virtually every concept can minimally be ascribed to a word in each language and word forms can be ambiguous across languages. For example, in Spanish, un vaso is a drinking glass, but the word form looks strikingly like the English word vase. While these concepts are distinct, I use traditional psycholinguistic methods, including eye-tracking, to demonstrate that even highly proficient bilinguals experience momentary competition between conflicting meanings in the irrelevant language during spoken comprehension (Titone, Mercier, Sudarshan, Pivneva, Gullifer, & Baum, 2020), written comprehension (Gullifer, Kroll, & Dussias, 2013; Gullifer & Titone, 2019, and production (Dussias, Gullifer, & Poepsel, 2016; Gullifer et al., 2013).