formative

UK: /ˈfɔː^rmətɪv/ US: /ˈfɔrmətɪv/ ,(fôr′mə tiv)

WordReference Random House Learner's Dictionary of American English © 2025

form•a•tive /ˈfɔrmətɪv/   adj. [before a noun]

1. giving form or shape:
   a formative process in manufacturing.
2. relating to formation, growth, or development:
   a child's formative years.

See -form-.

WordReference Random House Unabridged Dictionary of American English © 2025

form•a•tive  (fôr′mə tiv), adj. 

1. giving form or shape;
   forming;
   shaping;
   fashioning;
   molding:
   a formative process in manufacturing.
2. pertaining to formation or development:
   a child's most formative years.
3. Developmental Biology [Biol.]
   • capable of developing new cells or tissue by cell division and differentiation:
     formative tissue.
   • concerned with the formation of an embryo, organ, or the like.
4. Grammar pertaining to a formative.

n. 

5. Grammar a derivational affix, particularly one that determines the part of speech of the derived word, as -ness, in loudness, hardness, etc.
6. Linguistics (in generative grammar) any element, as a word, affix, or inflectional ending, functioning as a minimal syntactic unit that can be used in forming larger constructions.

• Middle French formatif. See formation, -ive
• 1480–90

form′a•tive•ly, adv. 
form′a•tive•ness, n. 
Synonyms

• 2. receptive, impressionable, susceptible.

Collins Concise English Dictionary © HarperCollins Publishers::

formative / ˈfɔːmətɪv/ adjective

1. of or relating to formation, development, or growth: formative years
2. shaping; moulding: a formative experience
3. functioning in the formation of derived, inflected, or compound words

noun

1. an inflectional or derivational affix

ˈformatively adverb