No those are not Japanese words.
The scientific name of Ilang-ilang is Cananga odorata.
An ylang ylang is a fragrant flower of the tree Cananga odorata, or the essential oil derived from this flower.
Ylang ylang (Cananga odorata) is a dicot plant. It belongs to the family Annonaceae, which is a family of dicot flowering plants.
Ascalapha odorata was created in 1758.
Psydrax odorata was created in 1786.
Monotropsis odorata was created in 1817.
Pluchea odorata was created in 1826.
Reseda odorata was created in 1759.
Dipteryx odorata was created in 1802.
Cedrela odorata was created in 1759.
Chromolaena odorata was created in 1759.
The Russian name for Cananga latifolia is Kanangashirokolistnaya (Кананга широколистная). The English common name for this species is Cananga while the French name is also Cananga. The Khmer common name is Chhkè Sreng(ឆ្កែស្រែង). The Thai name for this species is similar to the Khmer name, Sakae saeng (สะแกแสง).The cananga occurs in Cambodia, Laos, Burma, Thailand, Vietnam, and Peninsular Malaysia. It is the tree with the height up to 20 m. tall. The flower of cananga is fragrant. The wood of the tree is used as febrifuge by the locals.