☞ The term is restricted to exogenous plants, and applied to one of the two grand divisions of these species, the other division including gymnosperms, or those which have naked seeds. The oak, apple, beech, etc., are angiosperms, while the pines, spruce, hemlock, and the allied varieties, are gymnosperms. [ 1913 Webster ]

2. An opening; an open space; a gap, cleft, or chasm; a passage perforated; a hole; as, an aperture in a wall. [ 1913 Webster ]

An aperture between the mountains. Gilpin. [ 1913 Webster ]

The back aperture of the nostrils. Owen. [ 1913 Webster ]

3. (Opt.) The diameter of the exposed part of the object glass of a telescope or other optical instrument; as, a telescope of four-inch aperture. [ 1913 Webster ]

☞ The aperture of microscopes is often expressed in degrees, called also the angular aperture, which signifies the angular breadth of the pencil of light which the instrument transmits from the object or point viewed; as, a microscope of 100° aperture. [ 1913 Webster ]

2. The practice of aping; an apish action. Coleridge. [ 1913 Webster ]

This feeling has been called by philosophers the apperception or consciousness of our own existence. Sir W. Hamilton. [ 1913 Webster ]

Things appertaining to this life. Hooker. [ 1913 Webster ]

Give it unto him to whom it appertaineth. Lev. vi. 5. [ 1913 Webster ]

The asperated part of its surface. Boyle. [ 1913 Webster ]

2. (Zool.) See Wateringpot shell. [ 1913 Webster ]

☞ By some applied to the natural order now called Boraginaceæ or borageworts. [ 1913 Webster ]