Dictionary
main line
noun
: an important highway or railroad line
Full Definition of MAIN LINE
1
: a principal highway or railroad line
2
slang : a principal vein of the circulatory system
See main line defined for English-language learners
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First Known Use of MAIN LINE
1841
Rhymes with MAIN LINE
A-line, affine, airline, align, alkyne, alpine, assign, at sign, balkline, baseline, beeline, benign, bloodline, blue line, blush wine, bovine, bowline, branchline, breadline, bright-line, buntline, bustline, byline, call sign, canine, caprine, carbine, carmine, cervine, chow line, clothesline, cloud nine, coastline, combine, compline, condign, confine, consign, corvine, cosign, cutline, dateline, deadline, decline, define, design, divine, dragline, driveline, earthshine, Einstein, eiswein, end line, enshrine, entwine, equine, ethyne, fall line, fault line, feline, ferine, first-line, flatline, flight line, foul line, fräulein, frontline, front line, goal line, gold mine, grapevine, guideline, hairline, hard-line, hard pine, headline, hemline, high sign, hipline, Holbein, hotline, ice wine, incline, indign, in fine, in-line, Irvine, jawline, jug wine, landline, land mine, lang syne, lifeline, load line, longline, lupine, mainline, malign, midline, moline, moonshine, neckline, off-line, old-line, online, opine, outline, outshine, ovine, Pauline, peace sign, Petrine, pipeline, piscine, pitch pine, plotline, plumb line, plus sign, pontine, porcine, potline, pound sign, propine, punch line, rapine, recline, redline, red pine, refine, reline, repine, resign, Rhine wine, ridgeline, roofline, Sabine, saline, Scotch pine, scrub pine, setline, shoreline, short line, sideline, sight line, skyline, snow line, soft-line, spring line, straight-line, strandline, straw wine, streamline, strip mine, strychnine, subline, sunshine, supine, syncline, taurine, tie-line, times sign, topline, touchline, towline, tramline, trapline, tree line, trephine, trotline, truckline, trunk line, tumpline, turbine, untwine, ursine, vespine, V sign, vulpine, waistline, white line, white pine, white wine, woodbine, yard line, zebrine, Z line
Medical Dictionary
main line
noun
Medical Definition of MAIN LINE
slang : a principal vein of the circulatory system
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