What is large; chief; -- applied to an extraordinary billow, supposed by some to be every tenth in order. [R.] Also used substantively. "Such decuman billows." Gauden. "The baffled decuman." Lowell called?

decuman — Large; chief; -- applied to an extraordinary billow, supposed by some to be every tenth in order. [R.] Also used substantively. "Such decuman billows." Gauden. "The baffled decuman." Lowell. (Webster's 1913.)

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