Way speed can be controlled (8)
I believe the answer is:
moderate
'be controlled' is the definition.
(thesaurus)
'way speed' is the wordplay.
'way' becomes 'mode' ('mode' can be a synonym of 'way').
'speed' becomes 'rate' (rate is a kind of speed).
'mode'+'rate'='MODERATE'
'can' acts as a link.
(Other definitions for moderate that I've seen before include "Read tome (anag) - unexceptional" , "Dare me to (anag) - act as an arbitrator" , "Average, middle rate" , "Within reasonable or average limits" , "So-so; sensible" .)