• apiranthes cernua,
• zpiranthes cernua,
• xpiranthes cernua,
• dpiranthes cernua,
• epiranthes cernua,
• wpiranthes cernua,
• soiranthes cernua,
• sliranthes cernua,
• s-iranthes cernua,
• s0iranthes cernua,
• spuranthes cernua,
• spjranthes cernua,
• spkranthes cernua,
• sporanthes cernua,
• sp9ranthes cernua,
• sp8ranthes cernua,
• spieanthes cernua,
• spidanthes cernua,
• spifanthes cernua,
• spitanthes cernua

The adjective form of the word "Spiranthes cernua" is "cernuous".

The plural form of "Spiranthes cernua" is "Spiranthes cernua." This is because "Spiranthes cernua" is a scientific name that follows the rules of binomial nomenclature, where the genus (Spiranthes) is always capitalized and the species (cernua) is lowercase. In scientific naming conventions, the plural form of a species name remains the same as the singular form.

The singular form of the word "Spiranthes cernua" is "Spiranthes cernua". The word is already in its singular form. It is a botanical name for a specific species of orchid commonly known as the "nodding ladies'-tresses".