The plural of cactus is cactuses or cacti.
A thick-stemmed plant of the Cactaceae family, typically bearing spines and lacking leaves. They are native to arid areas of North and South America.
The word "cactus" comes from the Latin word "cactus", which was derived from the Greek word "kaktos", both of which mean "cardoon" or "thistle".
The word "cactus" was first used to refer to a specific type of plant that belongs to the family Cactaceae, which is characterized by its thick, fleshy stems and spines.
The plural of "cactus" can be either "cactuses" or "cacti". Both forms are correct, although "cacti" is more commonly used in scientific or technical contexts, while "cactuses" is more commonly used in general or casual contexts.
The word cactus is singular but can occasionally used in the plural in American English but not British English.
As the word cactus has a Latin root, the correct plural form of cactus is cacti according to the Latin rule of replacing -us with -i.
The plural for cactus can also be formed in the standard English way of adding an -es suffix to any noun ending in s. Thus the word cactuses is also an acceptable way of writing the plural of cactus.
As the graph below shows, the word cacti is more commonly used in written English although both are perfectly correct and it is ultimately down to personal preference as to which plural form of cactus to use.
Here are some examples:
The graph shows the occurances of the plural of cactus in written English since 1800 using Google's Ngram Viewer.
Cacti are tough plants. Despite being able to survive in extremely arid conditions, some species of cactus can live to be 200 years old!