Insect is the correct spelling.
Insect.
There is no actual "opposite" of an insect. However, the other insect-sized arthropods are the arachnids (spiders and scorpions).
They spell the word "tick" (a biting insect, or a clock sound).
The household insect pest is a "cockroach".
That is the correct spelling of the insect, the silkworm.
The insect is a cicada. (family includes the co-called 17-year locust)
Tick.
The spelling of the flying insect name is the damselfly.
The correct spelling of the biting insect is mosquito.
The correct spelling is "insectivores" (insect eaters).
Cicada is the name of the insect you are looking for.
it's called an Entomologist and this is how you spell scientist