A period of time during which something is delayed or behind schedule.

देर

English Usage: There was a lag in the delivery of the package.

Hindi Usage: पैकेज की डिलीवरी में देर हुई।

To fall behind in movement, progress, or development.

पिछड़ जाना

English Usage: He began to lag behind the group during the hike.

Hindi Usage: वह यात्रा के दौरान समूह से पिछड़ गया।