weed āļāļ·āļāļāļ°āđāļĢ weed āļāļ·āļāļāļ°āđāļĢ The leaves or stems of a plant as distinguished from the seeds: dill weed. A plant considered undesirable, unattractive, or troublesome, especially one growing where it is not wanted, as in a garden.Rank growth of such plants. A water plant, especially seaweed.Something useless, detrimental, or worthless, especially an animal unfit for breeding.Slang Tobacco.Slang A cigarette.Slang Marijuana.To clear of weeds.To remove (weeds). Often used with out: weed out dandelions. To eliminate as unsuitable or unwanted. Often used with out: weed out unqualified applicants. To remove weeds.A token of mourning, as a black band worn on a man's hat or sleeve.The black mourning clothes of a widow.An article of clothing; a garment. Often used in the plural.