*penta*

n. Lack of repentance; impenitence. Bp. Montagu.

pref. [ Gr. penta-, a later combining form of pe`nte five. See Five. ] 1. A combining form denoting five; as, pentacapsular; pentagon. [ 1913 Webster ]

2. (Chem.) Denoting the degree of five, either as regards quality, property, or composition; as, pentasulphide, containing five sulfur atoms; pentoxide, containing five oxygen atoms, etc. Also used adjectively. [ 1913 Webster ]

a. [ Penta- + basic. ] (Chem.) Capable of uniting with five molecules of a monacid base; having five acid hydrogen atoms capable of substitution by a basic radical; -- said of certain acids. [ 1913 Webster ]

a. [ Penta- + capsular. ] (Bot.) Having five capsules. [ 1913 Webster ]

n. [ NL. See Penta-, and Achenium. ] (Bot.) A dry fruit composed of five carpels, which are covered by an epigynous calyx and separate at maturity. [ 1913 Webster ]

n. [ Penta- + chloride. ] (Chem.) A chloride having five atoms of chlorine in each molecule; as, phosphorus pentachloride. [ 1913 Webster ]

n. [ L. pentachordus five-stringed, Gr. penta`chordos; penta- five + chordh` string. ] 1. An ancient instrument of music with five strings. [ 1913 Webster ]

2. An order or system of five sounds. Busby. [ 1913 Webster ]

a. [ Penta- + acid. ] (Chem.) Capable of neutralizing, or combining with, five molecules of a monobasic acid; having five hydrogen atoms capable of substitution by acid residues; -- said of certain complex bases. [ 1913 Webster ]

n. [ Gr. pe`nte five. ] A five-pointed star, also called a pentagram or pentalpha. See illustr. under pentalpha. Sometimes referring to a similar figure, such as the figure composed of two equilateral triangles intersecting so as to form a six-pointed star. It was used in early ornamental art, and also with superstitious import by the astrologers and mystics of the Middle Ages. The six-pointed star is more comonly called a hexagram, or called Solomon's seal; it resembles the star of David (Magen David) [ 1913 Webster + PJC ]

a. [ See Penta-, Coccus. ] (Bot.) Composed of five united carpels with one seed in each, as certain fruits. [ 1913 Webster ]

n. (Gr. Antiq.) See Penteconter. [ 1913 Webster ]

n. (Physiol. Chem.) A red and purple pigment found in certain crinoids of the genus Pentacrinus. [ 1913 Webster ]

n. [ Penta- + Gr. kri`non a lily. ] (Zool.) Any species of Pentacrinus. [ 1913 Webster ]

n. [ Pentacrinus + -oid. ] (Zool.) An immature comatula when it is still attached by a stem, and thus resembles a Pentacrinus. [ 1913 Webster ]

‖n. [ NL. See Penta-, and Crinum. ] (Zool.) A genus of large, stalked crinoids, of which several species occur in deep water among the West Indies and elsewhere. [ 1913 Webster ]

n.; pl. L. Pentacra E. Pentacrons [ NL., fr. Gr. pe`nte five + 'a`kron a summit. ] (Geom.) A solid having five summits or angular points. [ 1913 Webster ]

n. [ Penta- + acrostic. ] A set of verses so disposed that the name forming the subject of the acrostic occurs five times -- the whole set of verses being divided into five different parts from top to bottom. [ 1913 Webster ]

n. [ Gr. penta`s penta`dos, a body of five, fr. pe`nte five. ] (Chem.) Any element, atom, or radical, having a valence of five, or which can be combined with, substituted for, or compared with, five atoms of hydrogen or other monad; as, nitrogen is a pentad in the ammonium compounds. [ 1913 Webster ]

2. Any grouping of five things. [ PJC ]

a. (Chem.) Having the valence of a pentad. [ 1913 Webster ]

{ } a. [ Gr. pentada`ktylos with five fingers or toes. See Penta-, and Dactyl. ] 1. (Anat.) Having five digits to the hand or foot. [ 1913 Webster ]

2. Having five appendages resembling fingers or toes. [ 1913 Webster ]

a. [ Pentadactyl + -oid. ] (Anat.) Having the form of, or a structure modified from, a pentadactyl limb. [ 1913 Webster ]

n. [ Penta- + Gr. de`ka ten. ] (Chem.) A hydrocarbon of the paraffin series, (C15H32) found in petroleum, tar oil, etc., and obtained as a colorless liquid; -- so called from the fifteen carbon atoms in the molecule. [ 1913 Webster ]

a. [ Penta- + decatoic. ] (Chem.) Of, pertaining to, or derived from, pentadecane, or designating an acid related to it. [ 1913 Webster ]

a. [ Penta- + decylic. ] (Chem.) Same as Quindecylic. [ 1913 Webster ]

a. [ Penta- + Gr. 'adelfo`s brother. ] (Bot.) Having the stamens arranged in five clusters, those of each cluster having their filaments more or less united, as the flowers of the linden. [ 1913 Webster ]

a. [ Penta- + root of L. findere to split. ] (Bot.) Divided or cleft into five parts. [ 1913 Webster ]

n. [ Penta- + -glot, as in polyglot. ] A work in five different tongues. [ 1913 Webster ]

n. [ Gr. penta`gwnon; penta- (see Penta-) + gwni`a angle: cf. L. pentagonium, F. pentagone. ] (Geom.) A plane figure having five angles, and, consequently, five sides; any figure having five angles. [ 1913 Webster ]

Regular pentagon, a pentagon in which the angles are all equal, and the sides all equal. [ 1913 Webster ]

a. [ Cf. F. pentagonal, pentagone, L. pentagonus, pentagonius, Gr. &unr_;. ] Having five corners or angles. [ 1913 Webster ]

Pentagonal dodecahedron. See Dodecahedron, and Pyritohedron. [ 1913 Webster ]

adv. In the form of a pentagon; with five angles. Sir T. Browne. [ 1913 Webster ]

a. Pentagonal. [ 1913 Webster ]

n. [ Gr. &unr_;, neut. of &unr_; having five lines. See Penta-, and -gram. ] A pentacle or a pentalpha. “Like a wizard pentagram.” Tennyson. [ 1913 Webster ]

{ } a. [ Corrupted fr. pantographic, -ical. ] Pantographic. See Pantograph. [ 1913 Webster ]

‖n. pl. [ NL., fr. Gr. &unr_; (see Penta-) + &unr_; female. ] (Bot.) A Linnæan order of plants, having five styles or pistils. [ 1913 Webster ]

{ } a. (Bot.) Of or pertaining to plants of the order Pentagyna; having five styles. [ 1913 Webster ]

a. Having five sides; as, a pentahedral figure. [ 1913 Webster ]

a. Pentahedral. [ R. ] [ 1913 Webster ]

n. [ Penta- + Gr. "e`dra seat, base.] A solid figure having five sides. [1913 Webster]

a. Pentahedral. Woodward. [ 1913 Webster ]

n. (Zool.) A peculiar insectivore (Ptilocercus Lowii) of Borneo; -- so called from its very long, quill-shaped tail, which is scaly at the base and plumose at the tip. [ 1913 Webster ]

‖n. [ NL., fr. Gr. &unr_;: cf. F. pentalpha. See Penta-, and Alpha. ] A five-pointed star, resembling five alphas joined at their bases; -- used as a symbol. [ 1913 Webster ]

‖n. pl. [ NL. See Pentamerous. ] (Zool.) An extensive division of Coleoptera, including those that normally have five-jointed tarsi. It embraces about half of all the known species of the Coleoptera. [ 1913 Webster ]

n. (Zool.) One of the Pentamera. [ 1913 Webster ]

a. [ Penta- + Gr. &unr_; part. ] 1. (Biol.) Divided into, or consisting of, five parts; also, arranged in sets, with five parts in each set, as a flower with five sepals, five petals, five, or twice five, stamens, and five pistils. [ 1913 Webster ]

2. (Zool.) Belonging to the Pentamera. [ 1913 Webster ]

‖n. [ NL. See Pentamerous. ] (Paleon.) A genus of extinct Paleozoic brachiopods, often very abundant in the Upper Silurian. [ 1913 Webster ]

Pentamerus limestone (Geol.), a Silurian limestone composed largely of the shells of Pentamerus. [ 1913 Webster ]

n. [ L., fr. Gr. &unr_;; &unr_; (see Penta-) + &unr_; measure. ] (Gr. & L.Pros.) A verse of five feet. [ 1913 Webster ]

☞ The dactylic pentameter consists of two parts separated by a diæresis. Each part consists of two dactyls and a long syllable. The spondee may take the place of the dactyl in the first part, but not in the second. The elegiac distich consists of the hexameter followed by the pentameter. Harkness. [ 1913 Webster ]

a. Having five metrical feet. [ 1913 Webster ]

n. [ Penta- + methylene. ] (Chem.) A hypothetical hydrocarbon, C5H10, metameric with the amylenes, and the nucleus of a large number of derivatives; -- so named because regarded as composed of five methylene residues. Cf. Trimethylene, and Tetramethylene. [ 1913 Webster ]