The character 武 (wǔ) was developed from Oracle bone script and is a combination character of which all parts convey the meaning.
The right side of the character is 戈 (gē), which was an axe-like weapon used in ancient times. The left side is the character 止 (zhǐ), or foot, that carries the same meaning as 腳 (jiǎo), and represents marching. Together, they make up the character 武 to show its original meaning, carrying weapons and marching into battle, or military.
The basic use of the character 武 is in combinations to describe martial or military action. For example, 武術 (wǔ shù) means martial arts and 比武 (bǐ wǔ), military or martial arts competition.
In other combinations, 武 defines nouns, using the construct of something or someone related to fighting, war, or martial arts, such as 武士 (wǔ shì), warrior, 武俠 (wǔ xiá), martial hero/knight errant, or 武官 (wǔ guān), officer or military attaché.
As an adjective, 武 combinations describe the brave, fierce, or even barbaric. For example, 英武 (yīng wǔ) means martial bearing, and 武斷 (wǔ duàn), arbitrary decision or high-handedness.