To inform someone in advance of a possible danger or problem.

चेतावनी देना

English Usage: I need to warn you about the slippery floor.

Hindi Usage: मुझे आपको फिसलन भरी जमीन के बारे में चेतावनी देनी है।

A notice or statement cautioning someone about a potential danger or problem.

चेतावनी

English Usage: She gave a warning about the approaching storm.

Hindi Usage: उसने आने वाली बारिश के बारे में चेतावनी दी।