Etymology The noun is possibly derived from dull or Middle English dold (past participle of dullen, dollen (“to make or become blunt or dull; to make or become dull-witted or stupid; to make or become inactive”), from dul, dol, dolle (“not sharp, blunt, dull; not quick-witted, stupid; lethargic, sluggish”); see further at dull), modelled after tantrum. The adjective is probably derived from the noun.
Were there no "tears and miseries," when the half-witted doldrums, thinking they were not big enough to be seen, put themselves on horseback, to bask and frolic in a procession, and meet their man-midwife, or surgeon, or whatever he is, who had left his business at Norwich, to go to London, for the purpose of administering their little nostrum to the Prince Regent?1817 April 30, William Hone, “Political Priestcraft, Continued, in another Epistle to the Rev. Dan[iel] Wilson, […]”, in Hone’s Reformists’ Register, and Weekly Commentary, volume I, number 15, London: Printed by J. D. Dewick, […]; published by William Hone, […], published 3 May 1817, →OCLC, columns 476–477:
Etymology The noun is possibly derived from dull or Middle English dold (past participle of dullen, dollen (“to make or become blunt or dull; to make or become dull-witted or stupid; to make or become inactive”), from dul, dol, dolle (“not sharp, blunt, dull; not quick-witted, stupid; lethargic, sluggish”); see further at dull), modelled after tantrum. The adjective is probably derived from the noun.
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Boring, uninteresting.
She quit her doldrum job and left to seek a life of adventure.