- Learn English
-
Learn grammar
-
List of words
-
Study your cards
-
Hang On, Man!
-
Audio Books
-
More apps
- Recent searches
-
above
-
island
-
rabbit-sized
-
petitioner
-
piggy
-
academic gown
-
stopwatch
-
coevolution
-
one c
-
length
- Hide translation
acorn tube
acorn tube /ˈeɪˌkɔrn tuːb/
noun
-
A small vacuum tube; used at high frequencies
(
acorn tube
)
a small vacuum tube; used at high frequencies