An Ethernet Network Interface Card, or NIC, can have an external AUI transceiver plugged into an Ethernet card (assuming it is an older 10base5 or combo 10base5 + 10baseT card), but most common NICs have them built into the card.
10baseT, which uses twisted-pair wiring, and 10base2, which uses thin coaxial cable attached to a Tee connector, have their transceivers built into their NIC. Some NICs have connections for both, and are called combo NICs
Transceiver is a combined word, taken from Transmitter and receiver. To save on manufacturing costs, a separate transmitter and receiver is combined into one package. This allows common modules to be shared between the transmitting portion and the receiving portion.
Refer to How Network Adapters Work and network topologies for additional information.