Lieutenant colonel

Lieutenant colonel, abbreviated LTC in NATO usage, is a military rank, in the middle of the "field grade" system that divides officers into junior, field, and general/flag. In the NATO designation system (STANAG 2116), it is level OF-4, which is equivalent to the naval rank of commander. It is U.S. officer grade O-5. The next lower rank is commonly, but not exclusively, "major". The next higher, again depending on the specific military organization, is "colonel".

In modern militaries, typical command assignments at this level would be a battalion. These are formations of 500-1000 troops, or smaller specialized units that require a high degree of responsibility for field operations. A lieutenant colonel might also be assigned to a head a staff section, such as a depiuty chief of staff (e.g., deputy chief of staff for intelligence (G-2)) for a division, or might be a specialist in higher staff. A lieutenant colonel also could be the executive officer (i.e., deputy commander) of a brigade.

In the U.S. military, rising to this rank, or the naval equivalent, and retiring, is the mark of a successful but not outstanding career.

Etymology

The term "colonel" derives from Latin from Middle French modification of Old Italian colonnello column of soldiers: colonel, diminutive of colonna column, from Latin columna . "Lieutenant", in this case, is a prefix meaning "assistant" or "assistant to".

Insignia

Many countries follow U.S. or British usages. In the U.S. military, a lieutenant colonel wears a silver oak leaf. The British and widespread Commonwealth usage has a crown and one diamond.

In the Russian system, a colonel (polkovnik) wears two small stars, much smaller than those of a general. Some other militaries use two diamons.