https://biblehub.com/text/hebrews/12-23.htm - Hebrews 12:23 -
pneumasi - G4151 (also plural) "TO [the] spirits [of the righteous, having been perfected]"
[the differing form accounting for the "TO"... else...]
[quoting] "The Hebrew counterpart (rûach) has the same range of meaning as 4151 (pneúma), i.e. it likewise can refer to spirit/Spirit, wind, or breath.]" [source: Bible Hub]