Main Difference
The main difference between Anteater and Aardvark is that the Anteater is a mammal suborder and Aardvark is a species of mammal.
Anteater
Anteater is a common name for the four extant mammal species of the suborder Vermilingua (meaning “worm tongue”) commonly known for eating ants and termites. The individual species have other names in English and other languages. Together with the sloths, they are within the order Pilosa. The name “anteater” is also colloquially applied to the unrelated aardvark, numbat, echidnas, pangolins and some members of the Oecobiidae.
Extant species are the giant anteater Myrmecophaga tridactyla, about 1.8 m (5 ft 11 in) long including the tail; the silky anteater Cyclopes didactylus, about 35 cm (14 in) long; the southern tamandua or collared anteater Tamandua tetradactyla, about 1.2 m (3 ft 11 in) long; and the northern tamandua Tamandua mexicana of similar dimensions.
Aardvark
The aardvark ( ARD-vark; Orycteropus afer) is a medium-sized, burrowing, nocturnal mammal native to Africa. It is the only living species of the order Tubulidentata, although other prehistoric species and genera of Tubulidentata are known. Unlike other insectivores, it has a long pig-like snout, which is used to sniff out food. It roams over most of the southern two-thirds of the African continent, avoiding areas that are mainly rocky. A nocturnal feeder, it subsists on ants and termites, which it will dig out of their hills using its sharp claws and powerful legs. It also digs to create burrows in which to live and rear its young. It receives a “least concern” rating from the IUCN, although its numbers seem to be decreasing.
Anteater (noun)
Any of several animals, in suborder Vermilingua, which are noted for eating ants and termites which they catch with their long sticky tongues.
Anteater (noun)
Any of some other unrelated species that feed with ants, including pangolin (scaly anteater), echidna (spiny anteater), aardvark and numbat (banded anteater).
Aardvark (noun)
The nocturnal, insectivorous, burrowing, mammal Orycteropus afer, of the order Tubulidentata, somewhat resembling a pig, common in some parts of sub-Saharan Africa. First attested in the late 18th c.
“The aardvark burrows in the ground and feeds mostly on termites, which it catches with its long, slimy tongue.”
Aardvark (noun)
A silly or credulous person who is prone to mistakes or blunders.
“I walked into the wrong bathroom like a total aardvark.”
Aardvark (noun)
a nocturnal badger-sized burrowing mammal of Africa, with long ears, a tubular snout, and a long extensible tongue, feeding on ants and termites.