‖n. [ L. ] A burden; an obligation. [ 1913 Webster ]

Onus probandi ety>[ L. ], the obligation to furnish evidence to prove an assertion; the burden of proof. [ 1913 Webster ]

adv. [ See On, prep. ] 1. Forward, in progression; onward; -- usually with a verb of motion; as, move on; go on; the beat goes on. “Time glides on.” Macaulay. [ 1913 Webster ]

The path is smooth that leadeth on to danger. Shak. [ 1913 Webster ]

2. Forward, in succession; as, from father to son, from the son to the grandson, and so on. [ 1913 Webster ]

3. In continuance; without interruption or ceasing; as, sleep on, take your ease; say on; sing on. [ 1913 Webster ]

4. Adhering; not off; as in the phrase, “He is neither on nor off, ” that is, he is not steady, he is irresolute. [ 1913 Webster ]

5. Attached to the body, as clothing or ornament, or for use. “I have boots on.” B. Gonson. [ 1913 Webster ]

He put on righteousness as a breastplate. Is. lix. 17. [ 1913 Webster ]

6. In progress; proceeding; ongoing; as, a game is on. [ 1913 Webster ]

☞ On is sometimes used as an exclamation, or a command to move or proceed, some verb being understood; as, on, comrades; that is, go on, move on. [ 1913 Webster ]

On and on, continuously; for a long time together. “Toiling on and on and on.” Longfellow. [ 1913 Webster ]

prep. [ OE. on, an, o, a, AS. on, an; akin to D. aan, OS. & G. an, OHG. ana, Icel. ā, Sw. å, Goth. ana, Russ. na, L. an-, in anhelare to pant, Gr. 'ana`, Zend ana. √195. Cf. A-, 1, Ana-, Anon. ] The general signification of on is situation, motion, or condition with respect to contact or support beneath; as: -- [ 1913 Webster ]

1. At, or in contact with, the surface or upper part of a thing, and supported by it; placed or lying in contact with the surface; as, the book lies on the table, which stands on the floor of a house on an island. [ 1913 Webster ]

I stood on the bridge at midnight. Longfellow. [ 1913 Webster ]

2. To or against the surface of; -- used to indicate the motion of a thing as coming or falling to the surface of another; as, rain falls on the earth. [ 1913 Webster ]

Whosoever shall fall on this stone shall be broken. Matt. xxi. 44. [ 1913 Webster ]

3. Denoting performance or action by contact with the surface, upper part, or outside of anything; hence, by means of; with; as, to play on a violin or piano. Hence, figuratively, to work on one's feelings; to make an impression on the mind. [ 1913 Webster ]

4. At or near; adjacent to; -- indicating situation, place, or position; as, on the one hand, on the other hand; the fleet is on the American coast. [ 1913 Webster ]

5. In addition to; besides; -- indicating multiplication or succession in a series; as, heaps on heaps; mischief on mischief; loss on loss; thought on thought. Shak. [ 1913 Webster ]

6. Indicating dependence or reliance; with confidence in; as, to depend on a person for assistance; to rely on; hence, indicating the ground or support of anything; as, he will promise on certain conditions; to bet on a horse; based on certain assumptions. [ 1913 Webster +PJC ]

7. At or in the time of; during; as, on Sunday we abstain from labor. See At (synonym). [ 1913 Webster ]

8. At the time of; -- often conveying some notion of cause or motive; as, on public occasions, the officers appear in full dress or uniform; the shop is closed on Sundays. Hence, in consequence of, or following; as, on the ratification of the treaty, the armies were disbanded; start on the count of three. [ 1913 Webster +PJC ]

9. Toward; for; -- indicating the object of some passion; as, have pity or compassion on him. [ 1913 Webster ]

10. At the peril of, or for the safety of. “Hence, on thy life.” Dryden. [ 1913 Webster ]

11. By virtue of; with the pledge of; -- denoting a pledge or engagement, and put before the thing pledged; as, he affirmed or promised on his word, or on his honor. [ 1913 Webster ]

12. To the account of; -- denoting imprecation or invocation, or coming to, falling, or resting upon; as, on us be all the blame; a curse on him. [ 1913 Webster ]

His blood be on us and on our children. Matt. xxvii. 25. [ 1913 Webster ]

13. In reference or relation to; as, on our part expect punctuality; a satire on society. [ 1913 Webster ]

14. Of. [ Obs. ] “Be not jealous on me.” Shak. [ 1913 Webster ]

Or have we eaten on the insane root
That takes the reason prisoner? Shak. [ 1913 Webster ]

☞ Instances of this usage are common in our older writers, and are sometimes now heard in illiterate speech. [ 1913 Webster ]

15. Occupied with; in the performance of; as, only three officers are on duty; on a journey; on the job; on an assignment; on a case; on the alert. [ 1913 Webster +PJC ]

16. In the service of; connected with; a member of; as, he is on a newspaper; on a committee. [ 1913 Webster ]

☞ On and upon are in general interchangeable. In some applications upon is more euphonious, and is therefore to be preferred; but in most cases on is preferable. [ 1913 Webster ]

17. In reference to; about; concerning; as, to think on it; to meditate on it. [ PJC ]

On a bowline. (Naut.) Same as Closehauled. --
On a wind, or
On the wind (Naut.), sailing closehauled. --
On a sudden. See under Sudden. --
On board,
On draught,
On fire, etc. See under Board, Draught, Fire, etc. --
On it,
On't, of it. [ Obs. or Colloq. ] Shak. --
On shore, on land; to the shore. --
On the road,
On the way,
On the wing, etc. See under Road, Way, etc. --
On to, upon; on; to; -- sometimes written as one word, onto, and usually called a colloquialism; but it may be regarded in analogy with into. [ 1913 Webster ]

They have added the -en plural form on to an elder plural. Earle. [ 1913 Webster ]

We see the strength of the new movement in the new class of ecclesiastics whom it forced on to the stage. J. R. Green. [ 1913 Webster ]

‖n.; pl. L. Onagri E. Onagers [ L. onager, onagrus, Gr. &unr_;. ] 1. (Rom. Antiq.) A military engine acting like a sling, which threw stones from a bag or wooden bucket, and was operated by machinery. Fairholt. [ 1913 Webster ]

2. (Zool.) A wild ass of central Asia, especially the koulan (Equus hemionus syn. Equus hemippus syn. Equus onager, formely Asinus onager). [ 1913 Webster +PJC ]

n. (Zool.) The dauw. [ 1913 Webster ]

n. A form of drum used by the Chippewa indians. [ Century Dict. 1906 ]

prop. n. (Bot.) Same as Oenothera, a genus of plants consisting of the evening primrose. [ PJC ]

n. The female of the onager. [ PJC ]

{ } a. [ From NL. Onagra an old scientific name of the evening primrose (Œnothera), fr. Gr. 'ona`gra a kind of plant; of uncertain origin. ] (Bot.) Pertaining to, or resembling, a natural order of plants (Onagraceae or Onagrarieae), which includes the fuchsia, the willow-herb (Epilobium), and the evening primrose (Œnothera). [ 1913 Webster ]

n. [ Onan (Gen. xxxviii. 9): cf. F. onanisme. ] Self-pollution; masturbation. [ 1913 Webster ]

‖n. (Zool.) A nocturnal South American monkey (Callithrix discolor), noted for its agility; -- called also ventriloquist monkey. [ 1913 Webster ]