Lance

"They're in standard formation, little bastards up front, big ones in back."

- Malta Station defense coordinator

A lance is the second smallest known organization of Covenant military units, with a file being the smallest known group.

Standard
A lance is usually commanded by a Sangheili Minor or Major Domo Sangheili, or a Jiralhanae Minor or Jiralhanae Major. A lance also contains a file of four Unggoy Minors and one Major. Sometimes, a Sangheili or Jiralhanae Major will oversee the command of three lances in a battle.

Kig-yar
A lance of Kig-yar usually consists and comprises of a group of four to six Kig-yar infantry, with one or two of them being Majors and the rest being Minors. Kig-yar lances are sometimes led by a Sangheili or a Jiralhanae, though this is not always the case.

Yanme'e
A lance of Yanme'e is usually nothing more than a swarm of around a dozen or so soldiers. As they are very mobile and constantly airborne, Yanme'e lances don't need to be commanded by a Sangheili. In Halo 2 and Halo 3, no leader can be distinguished within them.

Science Lance
Formed to recover and examine captured technology, science lances were dispatched by the Prophet of Regret in 2525 to the Damascus Testing Facility to study captured technology, although the MJOLNIR Armor had already been recovered by the SPARTAN-II supersoldiers.

Trivia

 * In the ancient world, a lance consisted of "A long wooden shaft with a pointed metal head, used as a weapon by knights and cavalry soldiers in charging."