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

530 syzygy, Nippon, coronagraph, Phoebus, heliocentric (3 letters)
531 stay, Atlas, fulcrum, foundation, sustentacular (7 letters)
532 marvel, ambush, unawares, camisado, Pearl Harbor (8 letters)
533 canvass, once-over, look-see, conspectus, questionnaire (6 letters)
534 gondola, pendant, hammock, adjourn, pensile (11 letters)
535 purple martin, aphagia, deglutition, San Juan Capistrano, gulp (7 letters)
536 natant, flipper, waterwings, modern pentathlon, J. Weismuller (8 letters)
537 axis, bilateral, hemihedral, radiate, point defect (8 letters)
538 mensal, gueridon, drop leaf, periodicity, centerpiece (5 letters)
539 scut, dock, caudad, anurous, pope's nose (4 letters)
540 inkle, ferret, Velcro, fast-forward, dub (4 letters)
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)

Answers: 530. sun, 531. support, 532. surprise, 533. survey, 534. suspend(ed), 535. swallow, 536. swimming, 537. symmetry, 538. table, 539. tail, 540. tape, 541. tax, 542. teacher, 543. telescope, 544. temperature,

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