<p><strong>Noun:</strong></p><ul><li>the bottom support of anything; that on which a thing stands or rests: a metal base for the table.</li><li>a fundamental principle or groundwork; foundation; basis: the base of needed reforms.</li><li>the bottom layer or coating, as of makeup or paint.</li><li>Architecture: the distinctively treated portion of a column or pier below the shaft or shafts.</li><li>the distinctively treated lowermost portion of any construction, as a monument, exterior wall, etc.</li><li>Botany, Zoology: the part of an organ nearest its point of attachment.</li><li>the point of attachment.</li><li>the principal element or ingredient of anything, considered as its fundamental part: face cream with a lanolin base; paint with a lead base.</li><li>that from which a commencement, as of action or reckoning, is made; a starting point or point of departure.</li><li>the main supporters or fans of a political candidate, celebrity, company, etc.: Her proposed policies are calculated to appeal to her base.</li><li>Baseball: any of the four corners of the diamond, especially first, second, or third base.</li><li>Compare home plate.</li><li>a square canvas sack containing sawdust or some other light material, for marking first, second, or third base.</li><li>a starting line or point for runners, racing cars, etc.</li><li>(in hockey and other games) the goal.</li><li>Military: a fortified or more or less protected area or place from which the operations of an army or an air force proceed.</li><li>a supply installation for a large military force.</li><li>Geometry: the line or surface forming the part of a figure that is most nearly horizontal or on which it is supposed to stand.</li><li>Mathematics: the number that serves as a starting point for a logarithmic or other numerical system.</li><li>a collection of subsets of a topological space having the property that every open set in the given topology can be written as the union of sets of the collection.</li><li>a collection of neighborhoods of a point such that every neighborhood of the point contains one from the collection.</li><li>a collection of sets of a given filter such that every set in the filter is contained in some set in the collection.</li><li>Also called base line.</li><li>Surveying: triangulation.</li><li>Painting: vehicle (def 10).</li><li>Also called carrier.</li><li>inert matter, used in the preparation of lakes, onto which a coloring compound is precipitated.</li><li>Photography: a thin, flexible layer of cellulose triacetate or similar material that holds the light-sensitive film emulsion and other coatings, especially on motion-picture film.</li><li>Chemistry: a compound that reacts with an acid to form a salt, as ammonia, calcium hydroxide, or certain nitrogen-containing organic compounds.</li><li>the hydroxide of a metal or of an electropositive element or group.</li><li>a group or molecule that takes up or accepts protons.</li><li>a molecule or ion containing an atom with a free pair of electrons that can be donated to an acid; an electron-pair donor.</li><li>any of the purine and pyrimidine compounds found in nucleic acids: the purines adenine and guanine and the pyrimidines cytosine, thymine, and uracil.</li><li>Grammar: the part of a complex word, consisting of one or more morphemes, to which derivational or inflectional affixes may be added, as want in unwanted or biolog- in biological.</li><li>Compare root (def 12), stem (def 16).</li><li>Linguistics: the component of a generative grammar containing the lexicon and phrase-structure rules that generate the deep structure of sentences.</li><li>Electronics: an electrode or terminal on a transistor other than the emitter or collector electrodes or terminals.</li><li>the part of an incandescent lamp or electron tube that includes the terminals for making electrical connection to a circuit or power supply.</li><li>Stock Exchange: the level at which a security ceases a decline in price.</li><li>Heraldry: the lower part of an escutcheon.</li><li>bases: Armor: a tonlet formed of two shaped steel plates assembled side by side.</li><li>Jewelry: pavilion (def 6).</li><li>in base: Heraldry: in the lower part of an escutcheon.</li></ul><p><strong>Adjective:</strong></p><ul><li>serving as or forming a base: The walls will need a base coat and two finishing coats.</li></ul><p><strong>Verb (used with object):</strong></p><ul><li>based, basing: to make or form a base or foundation for.</li><li>to establish, as a fact or conclusion (usually followed by on or upon): He based his assumption of her guilt on the fact that she had no alibi.</li><li>to place or establish on a base or basis; ground; found (usually followed by on or upon): Our plan is based on a rising economy.</li><li>to station, place, or situate (usually followed by at or on): He is based at Fort Benning. The squadron is based on a carrier.</li></ul><p><strong>Verb (used without object):</strong></p><ul><li>based, basing: to have a basis; be based (usually followed by on or upon): Fluctuating prices usually base on a fickle public's demand.</li><li>to have or maintain a base: I believe they had based on Greenland at one time.</li></ul>