1. Interaction.

Nuttall's Standard dictionary of the English language By Nuttall, P.Austin

• internly,
• interly,
• interely,
• interally,
• interlay,
• interpaly,
• interply,
• interplat,
• inter-play,
• interplayt,
• intrplay,
• intreplay,
• inturplay,
• interpley,
• interplei,
• interflwo,
• interelay,
• interple,
• interplae,
• interpled

• interiorize,
• interpellate,
• interleave,
• interchange,
• interlaced,
• intermural,
• interrupter,
• interfering,
• internal,
• interstate,
• interphone,
• interpret,
• interval,
• interpose,
• in theory,
• inderal,
• inter alia,
• interfere,
• interracial,
• intervenor,
• internship,
• interiorise,
• interim,
• interlace,
• interlope,
• in turn,
• interferon,
• interdepend,
• Interpol,
• interloper,
• in the raw,
• interior,
• interrupted,
• intercept,
• interfaith,
• interpolate,
• intermarry,
• interpreter,
• interweave,
• interfacial,
• in-tray,
• internalize,
• interface,
• interrelate,
• intern,
• interceptor,
• Interlaken,
• intercalate,
• interlacing,
• Interahamwe,
• internally,
• internalise,
• interlard,
• intertidal,
• interlayer,
• interne,
• interpreted,
• interaction,
• interactive,
• interact,
• intercalary,
• Interleaf,
• interbrain,
• interrupt,
• in the air.

The adverb form of "interplay" is "interplayfully".

The adjective form of the word "interplay" is "interplayful".

The plural of the "interplay" can be the "interplays".

The singular of the "interplay" can be the "interplay".