Definition - What does Data Collision mean?
A data collision is the result of simultaneous data packet transmission between two or more network domain devices or nodes. Data collision packets break into fragments and retransmitted.
Techopedia explains Data Collision
A node checks for network availability when attempting to transmit a data packet to another node. More than one network node may check the network simultaneously to verify that there are no active network transmissions and that signals are not in a channel transmission state. This mechanism is known as channel sensing.
Channel sensing facilitates simultaneous packet transmission by multiple nodes, which causes data collision and network noise. Other nodes that sense this noise use a backoff algorithm to avoid data collision.