Archaic. to take off or doff (one's hat), as in respect or submission.
Origin: 1300–50; ME valen, aph. var. of avalen (now obs.) < MF avaler to move down, v. deriv. of phrase a val down (lit., to the valley) (a to (< L ad) + valvale)
To doff (one's hat) as a token of respect or submission.
v.
intr.
To descend; lower.
To doff one's hat.
[Middle English valen, short for avalen, from Old French avaler, from aval, downward, from Latin ad vallem, to the valley : ad, to; see ad- + vallem, accusative of vallēs, valley; see wel-2 in Indo-European roots.]