The purpose of this study is to examine the ecolexicons of marine ornamental fish among fishermen in the Banyak Islands, Indonesia, focusing on naming conventions and their cultural significance. Using qualitative methods and ecolinguistic theory supported by semantic analysis, the research identifies 58 ecolexicons, categorized into groups such as anemonefish, surgeonfish, and butterflyfish. Data were collected through purposive and snowball sampling, with local fishermen as key informants. Findings reveal five naming criteria: resemblance (62%), distinctive features (31%), inventor/maker (9%), place of origin (9%), abbreviation (2%), and newly coined terms (7%). Notably, novel criteria emerged, including fish life stage, size, pidginization, and hybrid naming systems, prompting a reevaluation of Chaer's Inquisitive Semantics theory. The predominance of resemblance and distinctive traits in naming reflects the community's observational precision and ecological familiarity. The lexical choices are deeply rooted in cultural philosophy, expressed through ideological (conservatism), sociological (community norms), and biological dimensions. These interconnected influences shape how fishermen name and perceive marine life, reinforcing their bond with the local ecosystem. This study contributes to ecolinguistics by documenting unique naming practices and their sociocultural underpinnings, offering insights into how language encodes environmental knowledge. The findings underscore the importance of preserving indigenous lexicons as part of ecological and cultural heritage.