Henry —, child actor who played Elliott in 1982 family film ET: The Extra-Terrestrial (6)
I believe the answer is:
thomas
(Other definitions for thomas that I've seen before include "The Apostle who initially doubted the Resurrection" , "Sir - More, sixteenth century English statesman" , "Famous tank engine" , "- the Rhymer, C 13 Scots poet" , "-- Edison, inventor" .)