Dict: strongs - grateful

Strongs:

G2168 @ εὐχαριστέω eucharisteō yoo-khar-is-teh'-o From G2170; to be grateful that is (actually) to express gratitude (towards); specifically to say grace at a meal: - (give) thank (-ful -s).

G2169 @ εὐχαριστία eucharistia yoo-khar-is-tee'-ah From G2170; gratitude; actually grateful language (to God as an act of worship): - thankfulness (giving of) thanks (-giving).

G2170 @ εὐχάριστος eucharistos yoo-khar'-is-tos From G2095 and a derivative of G5483; well favored that is (by implication) grateful: - thankful.

G884 @ ἀχάριστος acharistos ach-ar'-is-tos From G1 (as a negative particle) and a presumed derivative of G5483; thankless that is ungrateful: - unthankful.