Adding a tetragram to each word turns it into a phrase for which the given definition is actually a useful definition. They are:
| What a definition can do | bE A GLoss | EAGL |
| What the Fonz does in his garden | hoE COOlly | ECOO |
| Show enthusiasm for Toledo and its surroundings | cheer NE OHio | NEOH |
| What a Katmandu fan might shout | gO NEPal | ONEP |
| Pulling a nickel from behind someone's ear, e.g. | cOIN Trick | OINT |
| Ranting about a stereo system | hiFI VEnting | FIVE |
| One who harvests Pekingese | doG REAper | GREA |
| What they did to fill the role of Columbo | casT FALk | TFAL |
| Rings up Laura Petrie, briefly | calLS MTm | LSMT |
| "The suit turned out to be polyester, not wool," say? | moTH IRony | THIR |
| Where your strong point runs out | forTE ENd | TEEN |
| Give new hope to McCartney and his band | hearTEN Wings | TENW |
| The fleet from Peru | limA SHIps | ASHI |
| The Big Book of Glue | pastiNG TOme | NGTO |
| German IT executive | boNN CTo | NNCT |
| Scripture for a Jewish standing stone | menHIR Torah | HIRT |
| An attempt to lurch | carEEN Try | EENT |
| Moishe Kaplan coming in | jeW ENTering | WENT |
| Heir to a cooking oil fortune? | boY WESson | YWES |
| Feature of five octopi | forTY ARms | TYAR |
| Field trip to see crops | farM OUTing | MOUT |
| What a plate sleeps on | disH MATtress | HMAT |
| "Kareem, meet the King" | leW, ELVis | WELV |
| Where a marathon branches | racE FORk | EFOR |
| The sphere you must attend to | duTY ORb | TYOR |
| Poach a great cat? | boIL LIon | ILLI |
| Mother of a Canadian province | mA ONTario | AONT |
| The Koran, sent via computer? | suFI FTp | FIFT |
| Bed for actor Martin | shEEN Sack | EENS |
| Annoy an anti-slavery insurrection leader | peEVE Nat | EVEN |
| "No, really, it was a fun evening...really." | parTY LIe | TYLI |
| Root vegetable on the network | tV ONIon | VONI |
| What O.J. wanted to do to the judge | whAM ITo | AMIT |
| Evening for a real estate charge | liEN NIght | ENNI |
| Walking stick, candy, or sugar | caNE TYpe | NETY |
| Boston suburb in the rain | weT ALLston | TALL |
| Result of a hurried Kazan film | eliA HASte | AHAS |
| Promiscuous newt | looSE EFt | SEEF |
| Standing in the doorway | haLF OUt | LFOU |
| Like an electric mermaid | paRT EEl | RTEE |
| I hate this flute! | damN FIFe | NFIF |
| A final Middle English letter | lasT YOGh | TYOG |
| Hint to finding minerals | loDE NUdge | DENU |
| Where to find twos | pasT ONEs | TONE |
| "Someone's at the door, dear" response | whO HONey | OHON |
| January time for seizing unpaid-for cars | rEPO Iap | EPOI |
| Get rid of Nolte | puNT NIck | NTNI |
| Increase the financial penalty | fiNE MOre | NEMO |
| Aspiration's stand-in for dangerous words | stUNT Aitch | UNTA |
| Blushing (only prettier) | goING Rose | INGR |
| Better than Calliope | abOVE Muse | OVEM |
| Drop your pants at Ireland | mOON Eire | OONE |
| Those like Winnie | poOHS Ilk | OHSI |
| Eisenhower, fielding for Montreal | eXPO Ike | XPOI |
| Resist gelling | doNT FIrm | NTFI |
| Active exhaust point | liVE VEnt | VEVE |
| Redwine's lawn | deaN TURf | NTUR |
| Place for coffee and polka music | tubA CAFe | ACAF |
| What to do when your trolley gets dirty | scOUR Tram | OURT |
| What they celebrate St. Patrick's day with in San Francisco | grEEN Fog | EENF |
| What they'll do if New Haven ends up underwater | shIFT Yale | IFTY |
The tetragrams spell out:
EAGLE, CO: ONE OH ONE POINT FIVE
GREAT FALLS, MT: THIRTEEN TEN
WASHINGTON, NC: THIRTEEN TWENTY
WEST YARMOUTH, MA: TWELVE FORTY
ORILLIA, ONT: FIFTEEN SEVENTY
LIVONIA, MI: TEN NINETY
TALLAHASSEE, FL: FOURTEEN FIFTY
OGDEN, UT: ONE OH ONE POINT NINE
MOUNTAIN GROVE, MO: ONE OH SIX POINT FIVE
VENTURA, CA: FOURTEEN FIFTY
These stations are, in order, KTUN, KEIN, WTOW, WBUR, CFOR, WCAR, WTAL, KKAT, KELE, KVEN. Skipping the first letters, these spell out "Tune in to WBUR for Car Talk at eleven."
Unfortunately, we were somewhat limited in what we could convince the Car Talk producers to let Click and Clack say. They did, however, refer to their "three-quarter-length hooded, car talk zippered sweatshirts," so the word referred to in the flavortext is "hooded." And, as the flavortext suggests, the past tense must be changed to third-person singular present. The answer is HOODS.
Training:
The reference to the boss's idiosyncratic speech at the end of the flavortext suggests that "Dialects" is the training needed. Hoods' 1999 album was ALONE, which is the answer.