grin 
/ˈgrɪn/ verb
grins; grinned; grin·ning /ˈgrɪn/ verb [no obj] : to smile widely
▪ She continued to tease her brother, grinning wickedly. ▪ He was grinning from ear to ear. [=he was grinning very broadly]
▪ She continued to tease her brother, grinning wickedly. ▪ He was grinning from ear to ear. [=he was grinning very broadly]
grin and bear it
: to accept something that you do not like because you have no choice
▪ I don't agree with their decision, but all I can do is grin and bear it.
▪ I don't agree with their decision, but all I can do is grin and bear it.
— grin noun, plural grins [count]
▪ He had/wore a foolish/sheepish/big grin on his face.
▪ He had/wore a foolish/sheepish/big grin on his face.
