Is Gibraltar in Majorca?

NO. Gibraltar is a British overseas territory on Spain's southern coast and has a land-border with the Spanish city of La Linea de la Concepción. Conversely, Majorca is one of Spain's Balaeric Islands off the east coast of the country. The two places are roughly 500 miles or 800 km apart as the crow flies.
Gibraltar is a small colony of United Kingdom in the Southern part of Spain.
Majorca is an island from the Balearic Archipelago, in the Mediterranean Sea. Majorca is a Spanish island.