slag

Everyday

1. (science) Rocky waste left over when metal is taken from ore. tree →
2. (UK, rude, offensive) An insulting word for a woman; never use it. tree →
3. slag off (UK, slang) To criticise someone rudely behind their back. tree →

In the lessons

In history and geography: slag heaps from old coal mines in Wales and northern England. In real speech children may hear «slag someone off», meaning saying nasty things. The insult is very rude and hurtful. Phrases: «slag heap», «slag off».

Examples

• The old mine left a huge slag heap. tree →
• Slag from the furnace was dumped by the river. tree →
• Stop slagging off your sister; it's unkind. tree →
• He slagged off the referee after the match. tree →
• The grey slag looked like rough stone. tree →
• Calling someone that word is rude and hurtful. tree →

Note

Rude sense: offensive, can get you in trouble; do not use it. «Slag off» is informal British and Irish slang. The science sense (waste from metal-making) is uncountable.