Answer: acab

AnswerCrossword Clue
ACABHail ...
ACABHail .. (call "Taxi!")
ACABHail ..
ACABCall ..
ACABWords after call or hail
ACABFlag down ..
ACAB"Okay, you're ..." (taxi joke punch line)
ACABHail .. (flag down a taxi)
ACABIt might be hailed
ACABHail ....
ACABHail ... (cry "Taxi!")
ACABHail -- (cry 'Taxi!')
ACABHail ... (wave from the sidewalk)
ACABSomething to hail or call
ACAB"Call me ..." (old joke setup)