Idiomatic tautologous doublets

I decided to collect up some examples of "tautologous doublets", by which I mean pairs of words which are commonly used together (idiomatic) but which actually mean the same thing. For example, "time and tide".

Sometimes these forms come from legal usage, where they may have been coined from two different languages (eg the latin and french terms for the same thing) for clarity, or where two terms may have been in common usage in two different contexts and the legal wording was designed to clearly apply to both existing contexts. Sometimes these forms are just poetic or rhetorical uses, of which some may have been coined by authors but others have arisen in the vernacular.

Many of these doublets exhibit some form of euphony (eg, "bits and bobs", "might and main", "out and about"). Some are connected with "and", some with "or" (eg, "let or hindrance"), some are hyphenated (eg, "higgledy-piggledy), and some have no conjunction at all (eg, "free gratis"). Most of them can be used only in the given order (they are unidiomatic if reversed) and with the given conjunction (ditto), and more than a few contain fossil words in that one or both of the words is nowadays used only in this idiomatic phrase and not independently (at least, not with the same sense).

Note that I am only collecting examples where the words really do mean the SAME. There are many more idiomatic phrases where the two words have similar or complementary meanings (eg, "here and there", "flesh and blood", "give and take", "neck and neck", "to and fro"). These are not tautologous as such, and so don't count.

PLEASE let me know any other examples you can think of to add to this list. ALSO let me know if any of these examples should be deleted (eg, because the two words are not quite synonyms). Thanks!

Here is my list to date:

1. True tautological doublets
These words all exist (or existed), and have been combined into the idiomatic phrase.

"above and beyond"
"aid and abet"

"apt and able" (thanks, Adrienne!)
"bag and baggage"
"beck and call"
"best and brightest" (thanks, Adrienne!)
"betwixt and between" (thanks, Adrienne!)
"bits and bobs"
"cease and desist"
"chop and change"
"clean and tidy"
"confound and confuse" (thanks, Adrienne!)
"damn and blast"

"down and out"
"each and every"
"fair and square"
"far and away"
"fast and furious"
"first and foremost"
"fits and starts"

"free and clear" (thanks, Adrienne!)

"free and easy"
"free gratis"
"fun and games" (thanks, Adrienne!)
"goods and chattels"
"hale and hearty"
"hard and fast"
"have and hold"

"by hook or by crook"
"hue and cry"

"hum and haw" (thanks, Adrienne!)

"kit and caboodle" (thanks, Adrienne!)

"kith and kin"
"let or hindrance"
"liens and encumbrances"
"might and main"
"null and void"
"odds and ends"
"one and the same"
"out and about"
"over and above"
"part and parcel"
"pick and choose"
"prim and proper"
"rack and ruin"
"rant and rave"
"right and title"
"rough and tumble"
"safe and sound"

"six of one and half a dozen of the other"
"sole and exclusive"
"spick and span"
"stuff and nonsense"
"terms and conditions"
"time and again" (thanks, Adrienne!)
"time and tide"
"tried and tested"

"up and about"
"vim and vigour" (thanks, Adrienne!)

"wait and tarry" (thanks, Adrienne!)

"ways and means"
"wear and tear"
"well and good"
"will and testament"

2. Exact reduplications

These repeat a word or syllable for emphasis or effect, which is a bit of a special case.

"bye bye"

"choo-choo"

"chop chop" (thanks, Adrienne!)

"fru fru" (thanks, Adrienne!)

"go-go" (thanks, Adrienne!)

"lu-lu" (thanks, Adrienne!)

"night night"

"no-no"

"poo-poo"

"so so" (thanks, Adrienne!)

"wee-wee"

3. Rhyming or ablaut reduplications

These repeat a word or syllable in a modified form, either rhyming or with a contrasting/modified vowel. They differ from the true tautological doublets in that the second word was formed as a reduplication rather than selecting an existing synonym. In some cases, the second word has later become a synonym, perhaps precisely because of the coining of the reduplicated form.

"bric-à-brac"

"chit-chat"

"clap-trap"

"criss-cross"

"ding-dong"

"flim flam" (thanks, Adrienne!)

"flip-flop"

"higgledy-piggledy"

"jibber-jabber"

"kitty-cat"

"knick knack"

"loosey goosey"

"namby-pamby"

"pitter-patter"

"razzle-dazzle"

"ring-a-ling" (thanks, Adrienne!)

"splish-splash"

"super-duper"

"teenie-weenie"

"teeter-totter" (thanks, Adrienne!)

"tick tock" (thanks, Adrienne!)

"tip top" (thanks, Adrienne!)

"wibbly wobbly"

"wishy washy" (thanks, Adrienne!)

"zig zag"

4. Some questionable cases

These are examples where it is unclear whether they are synonym doublets at all, because the exact meaning or origin of the phrase is lost in the mists of time, or is disputed

"between a rock and a hard place" (thanks, Adrienne!)

"cock and bull" (thanks, Adrienne!)

How many more can you find for me?