No, Hedy Lamarr invented a particular mechanical way to achieve frequency hopping spread spectrum (FHSS) using paper player piano rolls.
FHSS was actually invented by Tesla, who patented the idea in 1903, and there were various implementations of it by WWI.
Moreover, direct sequence spread spectrum (DSSS) was actually only made practical through the "noise wheel" work of Mortimer Rogoff around 1950. His work was kept secret for over 30 years, which is part of the reason why few people know of him.
Hedy Lamarr was clearly a very intelligent person, and her work with George Antheil was apparently used to control some torpedoes in the 1960's using FHSS.
But it is misleading to say that she invented spread spectrum, or even invented frequency hopping.
It should also be noted that only the lowest bandwidth early 802.11 protocols used FHSS. There was a transition to DSSS, and now most modern 802.11 protocols use OFDM.