Trusty Trout, Humble Trout, Old Trout: A Curious Kettle

Old trout‘ as a disparaging and dismissive term for an elderly woman is still with us, although used with a degree of archness, an affectation of the linguistic practices of an earlier time. 1 But the true, trusty, and humble trouts of earlier centuries, close friends and confidants, are a now extinct species. OED presents these as figurative uses of the ichthyonym trout, the common designation of Salmo fario. No explanation of how such extended meanings may have developed is offered. 2