os·cil·late 
/ˈɑ:səˌleɪt/ verb
os·cil·lates; os·cil·lat·ed; os·cil·lat·ing /ˈɑ:səˌleɪt/ verb [no obj] 1 : to move in one direction and then back again many times
▪ The fan was oscillating. [=was turning to the right, then to the left, then to the right, etc.] ▪ Stock prices have continued to oscillate. [=to go up and down] ▪ an oscillating fan 2 formal : to keep changing from one belief, feeling, condition, etc., to an opposite one — usually + between ▪ The mood of voters has oscillated between optimism and pessimism. ▪ The weather oscillated between brutal cold and searing heat. 3 technical : to change in strength or direction regularly
▪ an oscillating electric current ▪ oscillating radio waves ▪ stars that oscillate in brightness [=that get brighter, then fainter, then brighter, etc.]
▪ The fan was oscillating. [=was turning to the right, then to the left, then to the right, etc.] ▪ Stock prices have continued to oscillate. [=to go up and down] ▪ an oscillating fan
▪ an oscillating electric current ▪ oscillating radio waves ▪ stars that oscillate in brightness [=that get brighter, then fainter, then brighter, etc.]
