weak

The nail is soft. It bends easily and may peel in soft thin layers, or splinter at the tip and sides.

brittle

The nail tip often snaps off when the nail is hard and brittle. Flexibility has been lost; a common condition as we age.

discoloured

The nail is stained, dull or discoloured. It may have a yellowish tinge or be an unhealthy colour.

damaged

The nail surface has ridges running down the nail. Cracks can appear on the ridges and the nail surface may start to flake.