Noun

(en noun)

a railroad system where the trains run on one rail

a train running on a single rail

Noun

(en noun)

(business) A company operating in only one industry or line of business; often specifically a bank specializing in credit card issuance.

*{{quote-book, 2005, David Sparks Evans and Richard Schmalensee, Paying with Plastic citation

, passage=The other leading monolines in 2002 were Capital One and Providian.}}

(finance) An insurer specialized in insuring investment-grade securities against loss.

*{{quote-book, 2005, Charles Austin Stone and Anne Zissu, The Securitization Markets Handbook citation

, passage=The premium charged by the monoline is not for funding expected losses, as with insurance, but for enhancing an investment-grade security to a AAA level.}}

(calligraphy) A font line of consistent width, as occurs when imitating pencil script.

*{{quote-book, 1984, Margaret Shepherd, Calligraphy Now citation

, passage=

(aquaculture) A length of monofilament line, used for culturing forms of seaweed.

*{{quote-book, 1982, Jose Rodolfo Lim, Farming the Ocean (the Genu Story), page=73 citation

, passage=A module consists of 21 monolines'; a ' monoline on the other hand is 20 feet (6 m) long and consists of a nylon line plus 3 stakes— 2 at both ends and one at the middle— and 30 plants. }}

(printing, dated) A type of composing machine in which each line of type is cast as a single slug.

*{{quote-book, 1993, Rae Frances, The Politics of Work: Gender and Labour in Victoria 1880-1939, page=126 citation

, passage=With the straight matter being set on the linotype or monoline , the hand compositor was left with what he claimed was the most 'skilled' part of his old work.}}

(spectroscopy) A single spectrum line.

*{{quote-journal, 2007, V.A. Shabashov et al., Deformation-induced transformations in nitride layers formed in bcc iron, Materials Science and Engineering: A, volume=452, pages=575-583, doi=10.1016/j.msea.2006.11.071

, passage=The spectrum of the MS sample also includes the central broad singlet of the nitrous austenite, which is simulated as the superposition of a monoline and a doublet.}}