I want to thank many people for their contributions in reply to my survey.
On this list, in particular, I want to thank the following for contributing from their conlangs;
Jim Henry for Esperanto, "eldonejo"(= publishing house, literally "out-giving-place" )
(yes, I'm aware Jim Henry doesn't claim Esperanto as his conlang.)
Toki Pona  "tomo tawa"= automobile (lit. "house go").
(unspecified languag(s)) conventional kenning for "falsehood" that glosses as "devil's truth".
 "-jqa" means "something rotated 90 degrees from the referent of the root",
"swynx" = desk, table; "swynx-jqa" = shelf.

Andreas Johansson for a Meghean idiom: _techreuth rhuco_ ,
lit. "he/she has lost (his/her) feet",
meaning that is this someone procastrinates.
The idea, of course, is that if you've lost your feet, you can literally not get going.
R A Brown for "out-giving-place" --  could be a soup-kitchen  
instrument+receptacle+liquid+complement = 'corkscrew' 
Roger Mills for
Indonesian _rumah sakit_ (house+sick) 'hospital'
Kash house+health for  'hospital'
Kash verbs with prefix caka-,
caka/oni 'to nitpick, quibble' (oni 'test, try').
ca/kanjik 'gluttonous; s.o. who'll eat anything (fig. gullible)'
(hanjik 'bite of food, mouthful'). 
related ca/kacip 'picky about one's food; (fig.) fastidious',
vele ('give') hacip 'to give a small bribe/payoff' (hacip 'a little bite/nibble of food')
nonce-forms like caka/fanu 'obsessed with the number 8' (fanu '8').

Carsten Becker for Deutsche "abkupfern", to copy someone else's work for one's own purposes, i.e. steal intellectual property -- yes, I know that's a natlang, not Carsten's conlang
Carsten didn't say which conlang _Anguty!_ for "Thank You"
which is from _Ang cutyin!_ resp. _Cutyang!_ for "I thank".
caeruleancentaur for
"It is raining cats and dogs"
Equivalent expressions in other languages are more logical. 
Spanish: llueve a cntaros, it is raining by the buckets.
French: il pleut des hallebardes, it is raining halberds.
Italian: piove a catinelle, it is raining by the basins.
German: es regnet Bindfaden/Strippen/in Strmen, it is raining
threads/strings/in streams; es giet wie mit Mollen/Scheffeln, it
pours as if with beer-glasses (I love this one!)/bushels.

"It is raining cats and dogs"
rijrmi nimrsa.
rijr--m-i n-i-rs-a.
waterfall-great-mutative-pl.  it-pres. time-rain-indicative
great-waterfalls it-rains.
[dz)] = augmentative suffix.
= m_0

Senjecan(?) words all using "bear," as in ursus, as the modifier.
rlcin; ren, bear, + lcin, hungry = ravenous
rpltin; ren, bear, + pltin, wide = huge, enormous
rmvin; ren, bear, + mvin, toothed = grumpy
NOTE: = dz); c = k.
nouns based on the root _dmon_ from the verbnoun _dma_ build. 
-on tells us that it is a concrete noun related to the stem.  It means building.  
It can be any type of building that humans (or other intelligent beings) construct.
These nouns all denote buildings wherein the action of the verb takes place,
"building for assembling, building for imprisoning, etc."

crdmon > cra, buy, purchase = store. 
I had to make a decision here. 
Was a store a place for buying or selling?
jeexdmon > jca, heal = hospital. 
Another decision here: was a hospital a place to be sick or a place to be healed?
mndmon > mna, learn = school. 
Another decision here: was a school a place for teaching or for learning?
lmuuldmon > lon, glass & mla, plant = greenhouse.
nendmon > non, corpse & na, burn = crematory.

cntdmon > cnta, assemble = assembly hall, meeting house.
coldmon > cla, imprison = prison.
cddmon > cda, cast, found = foundry.
edmon > da, eat = restaurant.
tengooldmon > etnon, grain & gla, store = granary.
gooldmon > gla, store, garner = warehouse.
lddmon > lda, perform, act = theater.
liiqdmon > lga, model, throw = pottery.
miildmon > mla, grind, mill = mill.
admon > a, pledge, guarantee = pawnshop.
psddmon > psda, mint = mint.
poojdmon > pja, drink = tavern.
qoordmon > qra, tower up = tower.
cdmon > ca, defecate = latrine, outhouse.
vrdmon > vra, saw = sawmill.
vidmon > va, cooper = cooperage.
vosdmon > vsa, train naked, practice gymnastics = gymnasium.

veritosproject for:
> He doesn't have both oars in the water.
masola file "laasa".  masola fifu niasa.
hand-GEN-3PS go-COMMAND up-TOWARD.  hand-GEN-3PS go-PRESENT down-TOWARD.
He tells his hand to go up, but it goes down.

> He's a few bricks shy of a full load.
mesalafu soma.
hold-up-3PS-PRESENT building-ACCUSATIVE.
He is holding up a building.

> He couldn't pour piss out of a boot with the instructions printed on the
> heel.
nosila iosa.
blind-3PS sun-TOWARD.
He is blind to the sun.

> He's so dense, light bends around him.
laalo esa laalama.
God NEGATE lift-3PS-ACC.
God himself cannot lift him.
I also want to thank the following participants for contributions of idioms from natlangs;
Carsten Becker for German
"Es regnet Bindfden".
"Es pisst" (It's pissing).
"Es regnet wie aus Eimern/Kbeln" 
"Es regnet in Strmen"
Henrik Theiling for German
'Es giet'. 
'es schttet' (~'pours').
'Es plstert ['plE:st6t].'   'heavy rain'.
and Henrik Theiling again for West Greenlandic
a school is a 'reading-place' (atuarfik).
Herman Miller for
"I'm not clear"
"there we go" 
"can't seem to find"
(BTW Herman: Did you find out what an "implicature" is?
An implicature is anything that is inferred from an utterance but that is not a
condition for the truth of the utterance.
www.sil.org/linguistics/ GlossaryOfLinguisticTerms/WhatIsAnImplicature.htm 
Conversational implicature is a nonconventional implicature based on an addressees assumption that the speaker is following the conversational maxims ...
Hancher, "Grice's 'Implicature'" (1978)
A 1978 essay by Michael Hancher. An introductory essay aimed at a literary audience.
Yahya Abdal-Aziz for
20.  Weigh in with ... (Contribute.)
19.  Sweating like a pig. 
18. He can't lie straight in bed.
17.  It's coming down in buckets.  (Said of heavy rain.)
16.  Catch a cold, measles or other disease. 
15. Gunna catch me some shut-eye / some Zees.  (Meaning 'I'm going to sleep'; )
14.  Well, butter me and call me toast! (Expresses surprise.)
13.  Strewth!  (Old Australian oath, meaning 'God's Truth'.)
12.  Strike a light!  (Expresses surprise or amazement.)
11.  Let 'er down, Hughie!  (Encouraging rain.  Hughie, or Huey, usually pronounced You-ie, is the putative rain god.  Usually called on by rural folk.)
10.  Stone the crows!  (Yet Another Expression of Surprise.)
9.  It's only two miles as the crow flies.  (the straight line distance)
8.  He's six foot tall.  (for 'six feet'.  Occasionally you may still hear 'two mile' for 'two miles'.)
7.  As bright as a two-bob watch.  (Flashy and cheap;  a 'bob' was a shilling, which in 1966 converted to 10 cents of a decimal dollar.)
6.  He's not the full two-bob.  (The florin, or two-shilling piece, was made of high-grade silver.  It was a favourite target of 'shavers' who took a little silver from the edge of each coin for later resale.  The person compared to this shaved two-bob bit was allegedly mentally deficient.)
5.  He's a few sandwiches shy of (or short of) a picnic. (Another alleged idiot.)
4.  He's got kangaroos in the top paddock.  (This fella's trouble is that thoughts just bounce around in his head.)
3.  He took the king's shilling.  (He became a soldier.  Also: 'He went for a soldier.')
2.  This weather plays merry hell with my bones.  (An arthritic's complaint.)
1.  Flat out like a lizard drinking.
0. 'Go figure!'
"boldly weave buttongrass bridles for butterflies"
but didn't quite complete:
"All cats are grey in the dark"  (Yahya left out the "in the dark" part.)

Rene [log in to unmask] for
Dutch (expressing surprise):
Wat heb ik nou aan mijn fiets hangen?
What is hanging from my bike?

Roger Mills for
'pulling someone's leg',
'kick the bucket'

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