overspill

UK: /ˈəʊvə^rspɪl/ US: (v. ō′vər spil′; n. ō′vər spil′)

Inflections of 'overspill' (v): (⇒ conjugate)

The past form "overspilt" is mainly used in UK English. It is correct in US English, but rare.

overspills

v 3rd person singular

overspilling

v pres p

overspilled

v past (US & UK)

overspilt

v past (Mainly UK)

overspilled

v past p (US & UK)

overspilt

v past p (Mainly UK)

WordReference Random House Unabridged Dictionary of American English © 2025

o•ver•spill  (v. ō′vər spil′;n. ō′vər spil′), v., -spilled or -spilt, -spill•ing, n. 
v.i. 

1. to spill over.

n. 

2. the act of spilling over.
3. something that spills over.
4. [Brit.] overflow.

• over- + spill¹ 1850–55

Collins Concise English Dictionary © HarperCollins Publishers::

overspill noun / ˈəʊvəˌspɪl/

1. something that spills over or is in excess
2. (as modifier): overspill population

verb / ˌəʊvəˈspɪl/ ( -spills, -spilling, -spilt, -spilled)

1. (intransitive) to overflow