flat

n. level surface; level area of land; tone one half step lower than another (Music); apartment (British)

adv. levelly, evenly; certainly, absolutely; exactly; below the proper pitch (Music); without interest

adj. having a planar surface; deflated (about a tire); absolute; lying down, horizontal; spread out; tasteless; monotonous, dull; mat, not shiny; having a tone one half step lower (Music)

Flat or flats may refer to:FlatnessFlat (music), a type of musical symbol Flat (domicile), an apartmentFlats (theatre), flat pieces of theatrical sceneryFlats (USPS), an oversized letterFlat, Puy-de-Dôme, FranceFlat, Alaska, United StatesFlat, Missouri, United StatesThe Flats, Cleveland, Ohio, United StatesFlat Island, Hong Kong, People's Republic of ChinaFlat Brook, tributary of the Delaware River in Sussex County, New JerseyFlat River (North Carolina), river in Southern Person County, North CarolinaRacing flats, lightweight shoes used primarily for running a raceFlat (geometry), the generalization of lines and planes in an n-dimensional Euclidean spaceFlat, a space without curvature (formally, with zero curvature)Flats, women's shoes with almost no heel at allA flat tireFlat, an anagram or puzzle in verse, the primary form of wordplay before crosswords came along
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n. apartment, flat

1. Lacking any complex internal structure. "That bitty box has only a flat file system, not a hierarchical one." The verb form is flatten. Usually used pejoratively (at least with respect to file systems).
2. Said of a memory architecture like that of the VAX or Motorola 680x0 that is one big linear address space (typically with each possible value of a processor register corresponding to a unique address). This is a Good Thing. The opposite is a "segmented" architecture like that of the Intel 80x86 in which addresses are composed from a base-register/offset pair. Segmented designs are generally considered cretinous.
3. A flat domain is one where all elements except bottom are incomparable (equally well defined). E.g. the integers.
[Jargon File]

Used in the context of general equities.
Convertibles: earning interest  on the date of payment only.
General: having neither a  short  nor long position  in a stock. Clean.
Market: characterized by horizontal price movement, usually the result of low activity.
Equities: to execute without commission or markup.