Arclike can be replaced with several synonyms that convey a similar curvature or shape. One possible synonym is curve-shaped, which suggests a gentle or gradual curve, similar to the curve of a smile. Another synonym is crescent-shaped, which conveys a more pronounced curve that resembles the shape of a crescent moon. Other synonyms for arclike include bow-shaped, arched, curvilinear, and serpentine. These words all convey a sense of flow and movement, suggesting a graceful and fluid shape. Ultimately, the choice of synonym for arclike will depend on the context and the specific connotations that the writer wants to convey.