Biological process

T cell development involved in immune response, T cell differentiation during immune response, T lymphocyte differentiation during immune response, T-cell differentiation during immune response, T-lymphocyte differentiation during immune response

The process in which an antigenically naive T cell acquires the specialized features of an effector, regulatory, or memory T cell as part of an immune response. Effector T cells include cells which provide T cell help or exhibit cytotoxicity towards other cells.

Note that immunologists typically use the word 'development' to refer to cells of B or T cell lineages undergoing the process that GO describes as 'cell differentiation'.