Keyword
What KeyWord is found in the definitions of each of the following?

541 tallage, gabelle, toll, millage, scutage (3 letters)
542 sensei, docent, mentor, maestro, tutor (7 letters)
543 finder, photoheliograph, spyglass, Mount Palomar, Galileo Galilei (9 letters)
544 kelvin, cryogenics, wind-chill factor, thermocline, relative humidity (11 letters)
545 doloroso, signature, presto, time, retard (5 letters)
546 order of magnitude, bel, sawbuck, dime, Decalogue (3 letters)
547 rally, bisque, dedans, groundstroke, deuce (6 letters)
548 pithy, laconic, succinct, sententious, compendious (5 letters)
549 oblation, acknowledgement, appreciate, gratitude, ta (5 letters)
550 biohazard, Sword of Damacles, ultimatum, menace, saber rattling (6 letters)
551 bore, sublittoral, slack water, mud flat, estuary (4 letters)
552 bind, truss, secure, fasten, moor (3 letters)
553 tegular, imbricate, ceramic, clay, mosaic (4 letters)
554 ambeer, rappee, snuff, caporal, perique (7 letters)
555 john, biffy, commode, ballcock, chamber pot (6 letters)

Answers: 541. tax, 542. teacher, 543. telescope, 544. temperature, 545. tempo, 546. ten, 547. tennis, 548. terse, 549. thank, 550. threat, 551. tide, 552. tie, 553. tile, 554. tobacco, 555. toilet,

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