Q: What are some examples of idioms that include obsolete words?
A: These are called fossil expresions -- words that have dropped out of
common use but hang around in idioms. Not all of them are separate
words, some are part of other words or have prefixes or suffixes
attached. There are also words which have current meaning, but the
meaning in the idiom is unrelated to it.
idiom fossil meaning of fossil
swashbuckler buckler small shield
newfangled fangled siezed
rank and file file column
to and fro fro from
gormless gorm attention
hem and haw haw make the sound "haw"
hem and haw hem make the sound "hem"
hue and cry hue outcry
kit and kaboodle kaboodle collection
out of kilter kilter order
kith and kin kith friends
let or hindrance let hindrance
footpad pad highwayman
pratfall prat buttocks
rank and file rank row
raring to go raring enthusiastic
ruthless ruth compassion
short shrift shrift confession
spick-and-span span chunk of wood
spick-and-span spick nail (spike)
swashbuckler swash bluster or stagger
bank teller tell to count