A male member of the British Army who isn't an officer. An old-fashioned synonym is Tommy. Stereotypical characteristics of squaddies include:
-They regularly go out drinking; while out they shamelessly try to pull civilian girls and often start fights (with each other as well as with civilians)
-They're from working class backgrounds
-They left education aged 15 or 16
-They're fiercely patriotic and xenophobic
-They're overtly racist towards South Asians and people of Middle Eastern descent
-They're deeply prejudiced against Islam, Communism and liberalism
-They're homophobic, and call any man who shows any signs of effeminacy "a poof"
-They're cocky as fuck
Last time I went to that bar a squaddie tried to dance with my girlfriend; then when she rejected him, he and his squaddie mates beat the shit out of me.