A variety of bass (fish) having a small mouth(noun)
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Use "smallmouth" in a sentence
"My largest fish I ever caught was a 5lb 19in smallmouth bass that I caught right after catching the second largest fish I ever caught, an 18in 4. 5lb smallmouth bass just minutes before."
"The easiest fishing I've ever had was catching smallmouth from a little creek, they hit every lure I threw at them including a naked roundhead jig."
"September brings a shift in smallmouth diet from crayfish to baitfish."