A jack (in any of the senses referring to types of fish).
Any carnivorous freshwater fish of the genus Esox, especially the northern pike, Esox lucius.
A large haycock (“conical stack of hay left in a field to dry before adding to a haystack”).
A very long spear used two-handed by infantry soldiers for thrusting (not throwing), both for attacks on enemy foot soldiers and as a countermeasure against cavalry assaults.
A sharp, pointed staff or implement.
A position with the knees straight and a tight bend at the hips with the torso folded over the legs, usually part of a jack-knife.
Especially in place names: a hill or mountain, particularly one with a sharp peak or summit.
A gypsy, itinerant tramp, or traveller from any ethnic background; a pikey.
To equip with a turnpike.
To assume a pike position.
Often followed by on or out: to quit or back out of a promise.
To prod, attack, or injure someone with a pike.
To bet or gamble with only small amounts of money.