To be arranged so that a part of one object laying over part of another; as, the boards overlapped at their ends. [PJC]
To have the ending time of one period or process extend beyond the beginning time of another period or process; as, the lives of Theodore Roosevelt and Franklin Roosevelt overlapped by several decades. [PJC]

overlap, n.

The lapping of one thing over another; as, an overlap of six inches; an overlap of a slate on a roof. [1913 Webster]
An extension of geological beds above and beyond others, as in a conformable series of beds, when the upper beds extend over a wider space than the lower, either in one or in all directions. [1913 Webster]

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OXFORD DICTIONARY

overlap, v. & n.
--v. (-lapped, -lapping)
1 tr. (of part of an object) partly cover (another object).
2 tr. cover and extend beyond.
3 intr. (of two things) partly coincide; not be completely separate (where psychology and philosophy overlap).
--n.
1 an instance of overlapping.
2 the amount of this.

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THESAURUS

overlap

accord, accordance, affinity, agree, agreement, answer to, applique, arch over, assent, assort with, be consistent, be of one, be uniform with, bedizenment, bestraddle, bestride, bridge, check, chime, chorus, cohere, coherence, coincide, coincidence, compatibility, concert, concord, concordance, concur, conform, conform with, conformance, conformation, conformity, congeniality, congruence, congruency, congruity, consist with, consistency, consonance, consort, cooperate, cooperation, correspond, correspondence, dovetail, duplication, duplication of effort, embellishment, equivalence, expletive, extend over, extravagance, fall in together, fat, featherbedding, filling, fit together, flap, fly, frill, frills, frippery, gingerbread, go together, go with, hang over, hang together, harmonize, harmony, hit, hold together, imbricate, imbrication, interlock, intersect, intersection, jibe, jut, lap, lap over, lie over, lock, luxury, match, needlessness, oneness, ornamentation, overadornment, overarch, overhang, overlapping, overlay, overlayer, overlie, override, padding, parallel, parallelism, payroll padding, peace, pleonasm, prolixity, rapport, redundance, redundancy, register, register with, respond to, ride, self-consistency, shingle, sing in chorus, sort with, span, square, square with, stand together, superfluity, superfluousness, symmetry, sync, synchronism, tally, tautology, timing, uniformity, union, unison, unisonance, unnecessariness, verbosity

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ROGET THESAURUS

overlap

Clothing

VB invest, cover, envelope, lap, involve, inwrap, enwrap, wrap, fold up, wrap up, lap up, muffle up, overlap, sheath, swathe, swaddle, roll up in, circumvest, vest, clothe, array, dress, dight, drape, robe, enrobe, attire, apparel, accounter, rig, fit out, deck, perk, equip, harness, caparison, wear, don, put on, huddle on, slip on, mantle.

Transcursion

VB transgress, surpass, pass, go beyond, go by, show in front, come to the front, shoot ahead of, steal a march upon, steal a gain upon, overstep, overpass, overreach, overgo, override, overleap, overjump, overskip, overlap, overshoot the mark, outstrip, outleap, outjump, outgo, outstep, outrun, outride, outrival, outdo, beat, beat hollow, distance, leave in the lurch, leave in the rear, throw into the shade, exceed, transcend, surmount, soar, encroach, trespass, infringe, trench upon, entrench on, intrench on, strain, stretch a point, strain a point, cross the Rubicon.

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