It's just semantics... but I'll throw my hat into the ring nevertheless:
The "eavesdropping" attack happens when you capture unecrypted packets. From there, you could either try to hijack the session by inserting yourself into the local conversation (effectively launching a "MITM" attack) or completely independently of the local conversation attempt to impersonate the login session (effectively launching an "impersonation" attack).
The "eavesdropping" attack happens when you capture unecrypted packets. From there, you could either try to hijack the session by inserting yourself into the local conversation (effectively launching a "MITM" attack) or completely independently of the local conversation attempt to impersonate the login session (effectively launching an "impersonation" attack).