To run afoul of, to run against or come into collision with, especially so as to become entangled or to cause injury. [ 1913 Webster ]

2. To entangle or run against so as to impede motion. [ 1913 Webster ]

2. To make foul; to defile. [ Obs. ] Wyclif. [ 1913 Webster ]

My face is foul with weeping. Job. xvi. 16. [ 1913 Webster ]

2. Scurrilous; obscene or profane; abusive; as, foul words; foul language. [ 1913 Webster ]

3. Hateful; detestable; shameful; odious; wretched. “The foul with Sycorax.” Shak. [ 1913 Webster ]

Who first seduced them to that foul revolt? Milton. [ 1913 Webster ]

4. Loathsome; disgusting; as, a foul disease. [ 1913 Webster ]

5. Ugly; homely; poor. [ Obs. ] Chaucer. [ 1913 Webster ]

Let us, like merchants, show our foulest wares. Shak. [ 1913 Webster ]

6. Not favorable; unpropitious; not fair or advantageous; as, a foul wind; a foul road; cloudy or rainy; stormy; not fair; -- said of the weather, sky, etc. [ 1913 Webster ]

So foul a sky clears not without a storm. Shak. [ 1913 Webster ]

7. Not conformed to the established rules and customs of a game, conflict, test, etc.; unfair; dishonest; dishonorable; cheating; as, foul play. [ 1913 Webster ]

8. Having freedom of motion interfered with by collision or entanglement; entangled; -- opposed to clear; as, a rope or cable may get foul while paying it out. [ 1913 Webster ]

Foul anchor. (Naut.) See under Anchor. --
Foul ball (Baseball), a ball that first strikes the ground outside of the foul ball lines, or rolls outside of certain limits. --
Foul ball lines (Baseball), lines from the home base, through the first and third bases, to the boundary of the field. --
Foul berth (Naut.), a berth in which a ship is in danger of fouling another vesel. --
Foul bill, or
Foul bill of health, a certificate, duly authenticated, that a ship has come from a place where a contagious disorder prevails, or that some of the crew are infected. --
Foul copy, a rough draught, with erasures and corrections; -- opposed to fair or clean copy. “Some writers boast of negligence, and others would be ashamed to show their foul copies.” Cowper. --
Foul proof, an uncorrected proof; a proof containing an excessive quantity of errors. --
Foul strike (Baseball), a strike by the batsman when any part of his person is outside of the lines of his position. --
To fall foul, to fall out; to quarrel. [ Obs. ] “If they be any ways offended, they fall foul.” Burton. --
To fall foul of or
To run foul of. See under Fall. --
To make foul water, to sail in such shallow water that the ship's keel stirs the mud at the bottom. [ 1913 Webster ]

2. (Mil.) To incrust (the bore of a gun) with burnt powder in the process of firing. [ 1913 Webster ]

3. To cover (a ship's bottom) with anything that impered its sailing; as, a bottom fouled with barnacles. [ 1913 Webster ]

4. To entangle, so as to impede motion; as, to foul a rope or cable in paying it out; to come into collision with; as, one boat fouled the other in a race. [ 1913 Webster ]

2. To become entagled, as ropes; to come into collision with something; as, the two boats fouled. [ 1913 Webster ]

2. (Baseball) See Foul ball, under Foul, a. [ 1913 Webster ]

3. In various games or sports, an act done contrary to the rules; a foul stroke, hit, play, or the like. [ Webster 1913 Suppl. ]

2. an article of clothing made of foulard{ 1 }, such as a neckpiece. [ PJC ]

I foully wronged him; do forgive me, do. Gay. [ 1913 Webster ]

So foul-mouthed a witness never appeared in any cause. Addison. [ 1913 Webster ]