Something used to fill a cavity, stop a gap, complete a load or charge, make bulk or to bring something to a required solidity, etc.

concrete. Also plural. That which fills or is used to fill a cavity or vacant space, to stop a tooth or a hole, to make up a bank or road, the…

With adverbs, as filler-in, filler-up.

concrete. Material used to fill up a space in or around something; spec. material used to make a joint, piston, etc., watertight or airtight.

Something which serves to fill up.

That which serves to fill up a hollow or stop a gap.

The action of filling in (a vacant space); that which is used to fill up a hole or cavity. Also figurative.

With adverbs, as filler-in, filler-up.

something that serves to occupy an otherwise vacant space; spec. a brief or insignificant item in a newspaper or magazine.

= infilling, n. (various senses).

A man-made hollow microsphere, usually of glass or synthetic resin, esp. one of a kind used in bulk to provide insulation or buoyancy.

Also, material used for filling. Cf. fibrefill n. at fibre, n. additions, infill, n., loose-fill n. at loose, adj. n.2adv. compounds 2, and rock-fill…