Ŏb'ser-vā'tion, n.

n. [Lat. observatio, Fr. observation, Sp. observacion, It. osservazione.]

1. The act or power of observing or taking notice; the act of seeing, or of fixing the mind upon, any thing.
2. That which is observed or noticed; notion gained, or the gaining of notions, by observing.

In matters of human prudence, we shall find the greatest advantage by making wise observations on our conduct. Watts. 3. Hence, that which is said as what has been observed or noticed; a remark. “That’s a foolish observation.” Shak. To observation which ourselves we make We grow more partial for the observer’s sake. Pope. 4. Hence, also, an action involving special attention as its condition; performance of what is prescribed; adherence in practice; observance. He freed the Christian church from the external observation and obedience of legal precepts not formally moral. White. 5. (Science.) (a.) The act of recognizing and noting some fact or occurrence in nature, as an aurora, a corona, or the structure of an animal. More specifically, (b.) The act of measuring, with suitable instruments, some magnitude, as the time of an occultation, with a clock; the right ascension of a star, with a transit instrument and clock; the sun’s altitude, or the distance of the moon from a star, with a sextant; the temperature, with a thermometer, &c. ☞ When a phenomenon is scrutinized as it occurs in nature, the act is termed an observation. When the conditions under which the phenomenon occurs are artificial, or arranged beforehand by the observer, the process is called an experiment. Experiment includes observation. Astronomy is exclusively a science of observation; physics and chemistry, chiefly of experiment. Syn.—Observance; notice; attention; remark; comment; note. See OBSERVANCE.