A feather in cap

[feth -er] /ˈfɛð ər/
noun
one of the h-rny structures forming the princ-p-l covering of birds, consisting typically of a hard, tubular portion attached to the body and tapering into a thinner, stemlike portion bearing a series of slender, barbed processes that interlock to form a flat structure on each side.
kind; character; nature:
two boys of the same feather.
something like a feather, as a tuft or fringe of hair.
something very light, small, or trivial:
your worry is a mere feather.
archery. one of the vanes at the tail of an arrow or dart.
carpentry. a spline for joining the grooved edges of two boards.
masonry. see under plug and feathers.
a featherlike flaw, especially in a precious stone.
machinery, feather key.
archaic. attire.
obsolete, plumage.
verb (used with object)
to provide with feathers, as an arrow.
to clothe or cover with or as with feathers.
rowing. to turn (an oar) after a stroke so that the blade becomes nearly horizontal, and hold it thus as it is moved back into position for the next stroke.
aeronautics.

to change the blade angle of (a propeller) so that the chords of the blades are approximately parallel to the line of flight.
to turn off (an engine) while in flight.

verb (used without object)
to grow feathers.
to be or become feathery in appearance.
to move like feathers.
rowing. to feather an oar.
verb phrases
feather into, south midland u.s. to attack (a person, task, or problem) vigorously.
idioms
a feather in one’s cap, a praiseworthy accomplishment; distinction; honor:
being chosen cl-ss president is a feather in her cap.
birds of a feather. bird (def 15).
feather one’s nest, to take advantage of the opportunities to enrich oneself:
the mayor had used his term of office to feather his nest.
in fine / high feather, in good form, humor, or health:
feeling in fine feather.
ruffle someone’s feathers, to anger, upset, or annoy (another person).
smooth one’s ruffled / rumpled feathers, to regain one’s composure; become calm:
after the argument, we each retired to our own rooms to smooth our ruffled feathers.
related forms
featherless, adjective
featherlessness, noun
featherlike, adjective
feather
/ˈfɛðə/
noun
any of the flat light waterproof epidermal structures forming the plumage of birds, each consisting of a hollow shaft having a vane of barbs on either side. they are essential for flight and help maintain body temperature
something resembling a feather, such as a tuft of hair or gr-ss
(archery)

a bird’s feather or artificial subst-tute fitted to an arrow to direct its flight
the feathered end of an arrow, opposite the head

a strip, spline, or tongue of wood fitted into a groove
the wake created on the surface of the water by the raised periscope of a submarine
(rowing) the position of an oar turned parallel to the water between strokes compare square (sense 8)
a step in ballroom dancing in which a couple maintain the conventional hold but dance side by side
condition of spirits; fettle: in fine feather
something of negligible value; jot: i don’t care a feather
birds of a feather, people of the same type, character, or interests
feather in one’s cap, a cause for pleasure at one’s achievements: your promotion is a feather in your cap
(irish) not take a feather out of someone, not knock a feather out of someone, to fail to upset or injure someone: it didn’t take a feather out of him
verb
(transitive) to fit, cover, or supply with feathers
(rowing) to turn (an oar) parallel to the water during recovery between strokes, princ-p-lly in order to lessen wind resistance compare square (sense 41)
(in canoeing) to turn (a paddle) parallel to the direction of the canoe between strokes, while keeping it in the water, princ-p-lly in order to move silently
to change the pitch of (an aircraft propeller) so that the chord lines of the blades are in line with the airflow
(transitive) to join (two boards) by means of a tongue-and-groove joint
(intransitive) (of a bird) to grow feathers
(intransitive) to move or grow like feathers
feather one’s nest, to provide oneself with comforts, esp financial
see also feathers
derived forms
featherless, adjective
feather-like, adjective
feathery, adjective
word origin
old english fether; related to old frisian fethere, old norse fjöthr feather, old high german fedara wing, greek petesthai to fly, sanskrit patati he flies
feather
n.

old english feðer “feather,” in plural, “wings,” from proto-germanic -fethro (cf. old saxon fethara, old norse fioþr, swedish fjäder, middle dutch vedere, dutch veder, old high german fedara, german feder), from pie -pet-ra-, from root -pet- “to rush, to fly” (see pet-tion (n.)). feather-headed “silly” is from 1640s. feather duster attested by 1858. figurative use of feather in (one’s) cap attested by 1734.
v.

old english fiðerian “to furnish with feathers or wings,” from feðer (see feather (n.)). meaning “to fit (an arrow) with feathers” is from early 13c.; that of “to deck, adorn, or provide with plumage” is from late 15c. in reference to oars (later paddles, propellers, etc.) from 1740. phrase feather one’s nest “enrich oneself” is from 1580s. related: feathered; feathering.
feather
(fě’ər)

one of the light, flat structures that cover the skin of birds. a feather is made of a h-rny substance and has a narrow, hollow shaft bearing flat vanes formed of many parallel barbs. the barbs of outer feathers are formed of even smaller structures (called barbules) that interlock. the barbs of down feathers do not interlock. evolutionarily, feathers are modified scales, first seen in certain dinosaurs.
feather