武 wǔ martial; military
Made up of [止 zhǐ to stop; to prohibit; until; footprint radical 77, 戈 gē spear radical 62]Made with 8 strokes.
Contains 'spear' and 'foot' suggesting a soldier and hence somthing military. 'Foot' may however be read as 'stop' with the concept of military interceding to 'stop' violence
Ancient small seal form 
Related characters
Also uses 止 zhǐ component: 步 bù (a step) 齿 chǐ (tooth) 此 cǐ (this) 定 dìng (to set) 正 zhèng (correct) 走 zǒu (walk) 足 zú (foot)
Also uses 戈 gē component: 成 chéng (to succeed) 戴 dài (to respect) 或 huò (maybe) 戋 jiān (narrow) 我 wǒ (I (me)) 戊 wù (fifth (ordinal)) 载 zài (to carry) 藏 zàng (treasury) 战 zhàn (to fight) 找 zhǎo (to try to find)
Sounds same
五 wǔ (five) 午 wǔ (noon)Different tone
乌 wū (crow) 屋 wū (house) 无 wú (not to have) 勿 wù (do not) 戊 wù (fifth (ordinal)) 务 wù (affair) 物 wù (thing)Cities
武汉 Wuhan, Hubei武夷山 Wuyishan, Fujian
武威 Wuwei, Gansu
People
洪武帝 Emperor Hongwu孙武 Sun Wu