1. calling out to someone to get their attention
2. signaling to a taxi or vehicle to stop
3. praising or greeting enthusiastically

Examples

• She was hailing a taxi on the busy street corner.
• The crowd was hailing the returning hero with cheers.
• He’s hailing from Texas but now lives in California.
• The captain was hailing the approaching ship over the radio.
• They were hailing the new policy as a major breakthrough.
• I saw him hailing his friend across the parking lot.