Boris Johnson in his post-Brexit speech says, “This is no time to quail.” I’ve never heard this usage before (though much of what Johnson says is opaque to me). He seems to mean “Lose courage, become faint or feeble” but the OED marks it as “Now rare”.
Is it? Or asking another way, was it understood by British hearers without need of explanation?
My reading without looking it up was “This is no time for argument or dissent.”