1. joined by treaty, agreement, or common cause; united in partnership
2. related or similar in nature, character, or purpose
3. relating to the Allied forces in World War I or World War II
Usage: historical; capitalized when referring to specific military alliance

Examples

• The two countries formed an allied coalition against their common enemy.
• She works in marketing and other allied fields like public relations.
• The Allied forces landed in Normandy on D-Day.
• Biology and chemistry are closely allied sciences.
• The allied nations met to discuss their joint strategy.
• His company provides accounting and allied business services.
• The Allied powers defeated Germany in 1945.