For words with a * contestants must also know definitions.

446. Easter lily 
447. ebullition*
448. eccentricity*
449. echolalia
450. ecocide
451. econometrics*
452. ecophysiology
453. edema, oedema
454. educible*
455. effervescence
456. efficacy
457. effulgence*
458. egregiousness
459. eidolons
460. El Niño*
461. El Salvador
462. electorate*
463. elitism, élitism
464. ellipticity
465. elocution
466. emanate
467. embarkation
468. embellishment
469. embrasure
470. embryonic
471. emplacement
472. emulsible
473. en masse*
474. encephalitis
475. encroaches
476. endocrinology
477. endogamy
478. endorphin
479. ensconce
480. ensiform
481. ensilage*
482. enthrallment
483. entropy
484. eonian, aeonian
485. epidemiology
486. epigenous
487. epiphenomenon
488. epiphyte
489. episodic*
490. eponymous
491. epoxy
492. eristic*
493. erumpent
494. escapism*
495. escapology
496. escutcheon
497. esoteric
498. Estonia
499. ethos*
500. etiolate
501. eupeptic
502. eupnea*
503. eureka 
504. euripus
505. evangelist, Evangelist
506. evocative
507. ex libris*
508. exclamatory
509. execrate
510. executive privilege
511. exergue
512. exhortation*
513. exhumation
514. exigent
515. exonerate
516. expiate
517. expostulation*
518. extensor
519. exudation
520. exurbia
521. eye rhyme* - rhyme created using words that look similar but are not pronounced in a rhyming way
522. eyespot