Vince wrote:
"IOW, what length must an end fed wire be to exhibit the characteristics
of a "longwire" antenna?

When operating at 7 MHz, is a 240 foot long endfed wire considered to be
a longwire antenna?"

Vees, rhombics, and Beverage antennas are long wires according to Kraus.
The long wire is usually 2 WL or more.

240 feet is 1.7 WL at 7 MHz which is less than 2 WL.

Best regards, Richard Harrison, KB5WZI