Luxuriant and Luxurious are easily confused words and are often wrongly substituted with each other. Both are Adjectives but with different root words.
It is derived from the noun Luxuriance
Luxuriant means growing prolifically and being in abundance - luxuriant vines. It usually depicts excessiveness of growth - luxuriant hair
Adverb : Luxuriantly
It is derived from the noun Luxury
Luxurious means displaying richness and superiority (due to being costly) - luxurious home, liking luxuries and comforts - luxurious tastes, being extravagant luxurious holiday
Adverb : Luxuriously
Noun : Luxuriousness
Note : One can have a luxurious home but not a luxuriant home and similarly vegetation can be luxuriant but not luxurious
1. The first thing that strikes about Susan is her luxuriant hair.
2. The entry to the bunglow was through its luxuriant gardens.
3. My friend is extremely fond of his luxuriant moustache
1. The new hotel in the neighborhood caters to those who want something more luxurious.
2. Reema had no qualms about moving into a small apartment despite having lived in a luxurious house all her life.
3. I enjoyed the luxurious trip to Europe with my friends.