Definitions for "Grinning"
Keywords:  fray, weakly, flaw, threads, weft
A seam that has gaps where threads can be seen or the seam can be seen through is said to be grinning. A seam that grins is weakly stitched, and dirt can get into the seam to fray and weaken the threads.
a flaw in a fabric, especially a ribbed fabric, that occurs either when warp threads show through the covering weft threads or when the threads have slipped, leaving open spaces on either side.
Observed where the substrate shows through a subsequent coating.
The underlying substrate shows through the most recently applied coating. This can happen with an opaque coating, or with a woodstain system if the existing coating/timber and the top coat differ greatly in colour.
Visibility of carpet backing through the face, often between two adjoining tuft rows. May be caused by low pile yarn weight, off-gauge tufting machine parts, tuft row deflection, inadequate blooming of pile yarn, or carpet installation over sharp curves such as stair nosings.
a facial expression characterized by turning up the corners of the mouth; usually shows pleasure or amusement