Does 1,3‐dichloroallene show geometrical isomerism?
This is a chiral compound; it has two enantiomers.  This source defines "geometrical 8somerism" as isomerism involving different geometrical arrangements, and a pair of nonsuperimposable mirror images would seem to qualify.  But in the body they talk about about cis/trans or E/Z isomers, not chiral compounds.  The latter, which applies here, should be described by more precise terms like "enantiomers".