Definition of "overlap"

overlap

/ˌəʊvəˈlæp/

verb
third-person singular simple present overlaps, present participle overlapping, simple past and past participle overlapped
1. To extend over and partly cover something.
2. To co-occur, to happen at the same time.
3. To have an area, range, character or function in common.
  Quotations
  Memento unfolds over 22 scenes—or, more accurately, 22 strands of time, the main strand (in color) moving backward in increments, and another strand (in black and white) going forward, though the two overlap profoundly.
  2012 November 8, Scott Tobias, “Memento’s puzzle structure hides big twists and bigger profundities”, in The AV Club‎
4. (mathematics) Of sets: to have some elements in common.
5. (genetics) To have some similar nucleotide sequences.
noun
plural overlaps
1. Something that overlaps or is overlapped
2. (rugby) a situation in the game where an attacking line has more players in it than the defensive line coming to meet it. The attacking side may exploit the overlap by using their superior numbers to break the opposition's defensive line. If attackers outnumber defenders by more than one player this is often termed a two man overlap or three man overlap, etc. If the attacking side fails to break through usually due to poor execution, they are said to waste an overlap.
3. (insurance, pensions) The payment of a spouse's or other dependant's annuity benefits concurrently with the member's benefits, on death of the member during the guarantee period.